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transcript
Handbookof Medications for the
NCLEX-RN® ReviewMARGARET M. DAHLHAUSER, RN, PhDProfessor EmeritusSchool of NursingTennessee State UniversityNashville, Tennessee
McGRAW-HILL, INC.Medical Publishing Division
New York Chicago San Francisco Lisbon Madrid Mexico City
Milan New Delhi San Juan Seoul Singapore Sydney Toronto
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Contents
CHAPTER 1 INTRODUCTION TO MEDICATIONS 1
CHAPTER 2 PERIPHERAL NERVOUS SYSTEM AGENTS 6
CHAPTER 3 CENTRAL NERVOUS SYSTEM AGENTS 20
CHAPTER 4 DRUGS THAT AFFECT FLUID AND ELECTROLYTE BALANCE 35
CHAPTER 5 CARDIOVASCULAR DRUGS 42
CHAPTER 6 DRUGS THAT AFFECT THE BLOOD 56
CHAPTER 7 ENDOCRINE DRUGS 70
CHAPTER 8 DRUGS FOR INFLAMMATORY AND ALLERGIC DISORDERS 88
CHAPTER 9 RESPIRATORY TRACT DRUGS 98
CHAPTER 10 GASTROINTESTINAL DRUGS 105
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Contents ◆ iii
CHAPTER 11 OPHTHALMIC DRUGS 115
CHAPTER 12 CHEMOTHERAPY USED TO TREAT INFECTIOUS DISEASES 118
CHAPTER 13 ANTICANCER DRUGS 144
CHAPTER 14 IMMUNOSUPPRESSIVE DRUGS 150
CHAPTER 15 DRUG THERAPY FOR OSTEOPOROSIS 152
CHAPTER 16 DRUGS USED TO TREAT POISONING 156
Chapter
1 Introduction toMedications
Few areas relevant to nursing practice have expanded as rapidly as the area of drugtherapy. Many new drugs are marketed yearly, and there are frequent changes in howto use both recently developed and classic drugs as a result of research and experience.The same drug may be used to treat different conditions and diseases. Most drugs haveseveral names; the most common are the generic name and the trade name. The genericname is related to the chemical name and is independent of the manufacturer. Thetrade name is designated and patented by the manufacturer. In this handbook, the mostcommonly used name, whether trade or generic, will appear in boldface type. If bothnames are equally recognizable both will appear in boldface type. Administeringmedications to clients is a nurse’s important, and frequently primary, responsibility.The administration of medications is guided by the five rights: the right drug, the rightdose, the right client, by the right route, at the right time. To accomplish this goal, thenurse must be able to interpret drug orders accurately, select correct drug preparation,calculate drug dosage accurately, and use different routes of administration safely andaccurately. The nurse must also be able to document accurately and know about druginteractions and side effects as well as be able to teach the patient how to use drugsaccurately.
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DISPENSING MEDICATIONS
Each agency has a system for dispensing drugs. A commonly used method is the unit-dose system, in which most drugs are dispensed in single-dose or unit-dose packagescontaining, for example, one tablet or one capsule. Medication orders written by thephysician are first checked by the medical secretary, and a registered nurse (RN), and theorder is sent to the pharmacy. Pharmacy personnel place the medications in a containerthat is delivered to the nursing personnel, who distribute them to the client. Most hospitalsuse computerized mechanisms and a device to scan the patient’s arm band and thebarcodes on medications to ensure accuracy.
CALCULATING DRUG DOSAGE
A few drugs are ordered and measured in terms of units (U) or milliequivalents (mEq).Units are unique for each drug. Concentrations of insulin, heparin, and penicillin areexpressed in units; however, there is no relationship between a unit of insulin and a unitof heparin. These medications are usually ordered in the number of units per dose. Forexample, an order for NPH insulin 20 U SC every morning at 7 a.m. or heparin 2000 USC every 12 h will be labeled in the number of units per milliliter (U 100 insulin contains100 U/mL); heparin may have 1000, 5000, or 10,000 U/mL. Drugs such as potassiumchloride are ordered in the number of milliequivalents per dose and labeled in terms ofmilliequivalents per dosage (e.g., they may have 10, 20, or 30 mEq/mL).
Most physician’s medication orders are expressed in metric units of measure. If theamount of medication ordered is the same as that on the drug label, no calculations arerequired, and preparing the correct dose is a simple matter. For example, if the physicianorders codeine 20 mg PO, and the drug label reads “codeine 20 mg tablets,” it is clearthat one tablet is to be administered to the client.
What happens if the order calls for codeine 20 mg and only codeine 10 mg isavailable? Calculations are then necessary to determine how many codeine tablets areneeded to give a dose of 20 mg. This can be done by simple mathematics:
O
H= 20 mg (O)
10 mg (H)= 2 tablets codeine
When the order and label of the drug on hand are in different systems, the nurse’sfirst step is to change what is ordered into what is on hand, and then divide what isavailable into what is ordered. Simple mathematical methods for doing this are presentedin Appendix A of NCLEX Review.
The most commonly used system of measurement is the metric system, which usesgrams for weight and liters for volume. The apothecary system uses grains, minims,drams, ounces, pounds, pints, and quarts; the household system uses teaspoons, table-spoons, and drops. All three systems are used in the administration of drugs.
Introduction to Medications ◆ 3
COMMON ABBREVIATIONS
The current trend is to discourage use of abbreviations because of their statistical corre-lation to dosing errors. Most hospitals have a list of acceptable abbreviations, but theiruse is strictly limited.
MEDICATION, PREPARATION, METHOD OFADMINISTRATION, AND INTERACTIONS
Forms of systemic drugs include liquids, capsules, and tablets, as well as transdermal,IV, IM, and pump delivery. Some drugs are available in only one preparation or dosageform; others are available in several forms.
Route of administration affects drug actions and response times by influencing ab-sorption and distribution. The IV route is the most rapid and effective route becausethe drug is injected into the bloodstream, thus bypassing barriers to absorption. Manydrugs can be administered by the IM route; these produce action within a few minutesbecause muscles have an abundant blood supply. The oral route (PO) generally pro-duces slower drug action than parenteral routes. Absorption and action of topical drugsvary according to the specific method of administration. Transdermal forms of medica-tions are absorbed through the skin and include systemically absorbed nitroglycerin andscopolamine.
Some other methods of drug delivery are listed below.
� Pump delivery systems may be external (outside the skin) or implanted (under theskin) and are refillable.
� An implanted vascular access device may be used to deliver chemotherapy directlyto a cancerous organ. Medication is administered using a special needle (Huber)that fits into the implanted catheter.
� An external pump using a Hickman catheter may be used for systemic delivery(e.g., total parenteral nutrition [TPN]).
� In continuous venovenous hemodialysis, blood is pumped from a double lumenvenous catheter through a hemofilter and returned to the patient through the samecatheter. There is no arterial access required and the system can be set up, used,maintained, and terminated by critical care nurses. This system is increasingly beingused to manage acute renal failure.
� An implanted needle may also be used to deliver insulin at a set dosage and a set timeschedule, thus eliminating the need for SC insulin injections. The external pump isattached to the patient’s clothing and is used to deliver insulin through a catheter viaa needle inserted subcutaneously, usually in the abdominal area. Narcotic analgesicsmay be delivered by an external pump called a patient-controlled analgesic pump(PCAP); a peripheral line or a central IV line (e.g., Hickman catheter) is used with
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the PCAP. The advantages of a PCAP are that it provides prolonged parenteral ad-ministration, there is no delay in drug administration, it avoids repetitive injections,it delivers consistent drug levels, and it usually decreases the amount of analgesicused. Enteric-coated tablets and capsules are coated with a substance that is in-soluble in gastric juices, so these medications do not dissolve until they reach theintestine, thus avoiding gastric irritation and keeping the drug from being destroyedby gastric juices. Several controlled-release dosage forms (sustained-release tabletsand capsules) have been developed to allow less frequent administration and moreconsistent serum drug levels. These tablets or capsules should not be crushed foradministration. If the client cannot swallow them, contact the physician for adviceon another route of administration.
Some foods contain substances that react with certain drugs, for example, the inter-action between tyramine-containing foods and monoamine oxidase inhibitors (MAOIs).Tyramine causes the release of norepinephrine (a potent vasoconstrictive agent) fromthe adrenal medulla and sympathetic neurons. The MAOI slows the breakdown ofnorepinephrine. As a result of these two actions, the client may experience severehypertension.
Another common example is the potential interaction that may occur between oralanticoagulants such as warfarin (Coumadin) and foods containing vitamin K. Becausevitamin K antagonizes the action of oral anticoagulants, large amounts of green leafy veg-etables such as spinach may offset the effects of anticoagulants and predispose the clientto thromboembolic disease. Vitamin K is necessary for the production of prothrombin,an important clotting factor.
Body weight affects drug action mainly in terms of dosage. The ratio between theamount of drug given and the body weight influences drug distribution. The recom-mended dosage for many drugs is given in terms of grams or milligrams per kilogramof body weight. Most pediatric drug dosages are calculated with formulas that use bodyweight to determine the correct dosage.
Attitudes and expectations related to a particular drug may influence the client’sresponse, as can psychological conditions. In the placebo effect, for example, substancessuch as sodium chloride solution are sometimes given to clients addicted to analgesicnarcotics to satisfy a demand for the addicting drug. The client does not know he or shehas received placebo, and if the client believes the placebo is the real drug, he or she willusually respond as if given the actual medication.
The action of a particular drug may be increased or decreased by its interaction withanother drug in the body. Drugs may have an additive effect (e.g., alcohol taken withsedative drugs increases sedation).
Pathologic (disease) conditions often alter the effects of drugs. Severe liver failurewill cause certain drugs to remain in the body for long periods because the failingliver cannot break down the drug and excrete it. Narcotic analgesics must be given invery small doses to a client with severe liver failure; otherwise the client may sufferfrom overdose. Severe or chronic diarrhea will cause rapid loss of oral medications.Excretion of medications decreases with severe kidney disease. Hyperthyroidism andfever cause increased metabolism of drugs.
Introduction to Medications ◆ 5
Antagonism occurs when a drug decreases the effects of a group of drugs (e.g.,naloxone [Narcan], a narcotic antagonist). This drug may be given to relieve narcotic-induced respiratory depression caused by morphine, a narcotic analgesic.
VARIABLES INFLUENCING DOSAGEAND ACTIONS OF DRUGS
There are many variables that may influence the dosage and actions of drugs. The firststep in individualizing drug therapy is to assess such variables as the client’s age, disease,and current medications. While drug therapy should be integrated with other aspects ofhealth care, appropriate non-drug measures should be used to decrease the need fordrugs, to enhance the therapeutic effects of drugs, or to decrease any adverse effects.
One final note: Nursing implications are not listed for every drug in this book, butadverse side effects and client educational needs should be viewed as implications fornursing.
Chapter
2 Peripheral NervousSystem Agents
MUSCARINIC AGONISTS AND ANTAGONISTS� The muscarinic agonists are drugs that bind to muscarinic receptors and thereby
cause their activation.� Since nearly all muscarinic receptors are associated with the parasympathetic ner-
vous system, the responses to muscarinic agonists closely resemble those producedby stimulation of parasympathetic nerves.
� Because their effects resemble those of parasympathetic stimulation, muscarinicagonists are known alternatively as parasympathomimetic agents or cholinergicagents.
� The muscarinic agonists, represented by bethanechol (Urecholine), are drugs thatselectively mimic the effects of acetylcholine at muscarinic receptors.
ANTICHOLINERGIC AGENTS� The muscarinic antagonists are drugs that competitively block the action of acetyl-
choline at muscarinic receptors.
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Peripheral Nervous System Agents ◆ 7
� The muscarinic antagonists are also known as parasympatholytic, muscariniccholinergic blocking agents or anticholinergic drugs.
◆ Cholinergic Agents (Parasympathetic Nervous System)
Generic Name Trade Name
Bethanechol MyotonacholDesired effect: Myotonachol is given to contract the urinary bladder, causing bladder emptying.
Major side effects: Cardiac arrest, abdominal discomfort, diarrhea, nausea, vomiting, salivation,
urinary urgency, and sweating
Treatment: Myotonachol is used in the treatment of acute postpartum and postoperative
nonobstructive urinary retention and in retention due to neurogenic bladder.
Nursing implications: Administer myotonachol on an empty stomach to avoid nausea and vomiting;
monitor response to establish minimum effective dose; report diarrhea,
headache, and dizziness.
Edrophonium Tensilon (also used to diagnose myasthenia gravis)
Neostigmine ProstigminPyridostigmine MestinonDesired effects: Tensilon, Prostigmin, and Mestinon inhibit the breakdown of acetylcholine, so it
accumulates and has a prolonged effect.
Major side effects: These agents may cause seizures, excessive secretions, bronchospasm,
bradycardia, and abdominal cramps.
Treatment: They are used to increase muscle strength in symptomatic treatment of myasthenia
gravis, and for prevention and treatment of postoperative bladder distention
and urinary retention or ileus.
Pilocarpine PilocarDesired effect: It directly stimulates cholinergic receptors, resulting in decreased intraocular
pressure and miosis (abnormal contraction of the pupils).
Major side effects: Blurred vision, eye pain, and increased sweating
Treatment: It is used alone or with other agents in the treatment of glaucoma.
Nursing implications: The nurse needs to report severe side effects of profound dizziness, and instruct
the patient to arise from a lying position slowly to avoid dizziness due to
orthostatic hypotension.
� Atropine is the best known muscarinic antagonist. It is found naturally in a varietyof plants, including Atropa belladonna.
� Because of the presence of belladonna in, for example, Donnatal, it is referred toas a belladonna alkaloid.
� It is easier to understand responses to anticholinergic agents if you first knowabout the response to cholinergic agents. Cholinergic agents cause bradycardia,sweating, salivation, increased bronchial and gastric acid secretions, and an increasein gastrointestinal peristalsis.
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◆ Anticholinergic Agents
Generic Name Trade Name
Atropine No trade name
Desired effect: Increased heart rate (drug of choice for bradycardia); decreased GI and respiratory
secretions
Major side effects: Drowsiness, blurred vision, tachycardia, and dry mouth
Treatment: IM: Preoperative medication to inhibit salivation and excessive respiratory secretions;
treatment of bradycardia and syncope due to hyperactive carotid sinus reflex,
treatment of parkinsonism; relieves tremor and rigidity
PO: Adjunctive therapy in the management of peptic ulcer and irritable bowel
syndrome
Note: Atropine is contraindicated in clients with glaucoma, chronic obstructive pulmonary disease (COPD), cardiac
arrhythmias, myocardial ischemia, and impaired liver function.
Belladonna tincture DonnatalTreatment: Used to treat spastic colon (drug of choice for diverticulosis)
Desired effect: Provides peripheral anticholinergic/antispasmodic action and mild sedation
Major side effects: Urinary hesitancy and retention, blurred vision, tachycardia, and palpitation
Benztropine CogentinTreatment: Adjunctive treatment of all forms of Parkinson’s disease, including drug-induced
extrapyramidal effects (e.g., Haldol)
Desired effect: Blocks cholinergic activity in the CNS, which is partially responsible for the symptoms
of Parkinson’s disease; reduction of rigidity and tremors
Major side effects: Dry eyes, blurred vision, constipation, dry mouth, tachycardia
Glycopyrrolate RobinulDesired effect: Inhibits the action of acetylcholine at postganglionic sites
Major side effects: Blurred vision, tachycardia, dry mouth, constipation, and urinary hesitancy
Treatment: Used as a preoperative medication to inhibit salivation and excessive respiratory
secretions
Propantheline Pro-BanthineDesired effect: Competitively inhibits the muscarinic action of acetylcholine, resulting in decreased
GI secretions
Major side effects: Drowsiness, blurred vision, tachycardia, dry mouth, constipation, and urinary retention
Treatment: Adjunctive therapy in the treatment of peptic ulcer disease
Scopolamine • Hyoscine
Treatment: Reduction of nausea and vomiting associated with motion sickness and depressing
salivary and bronchial secretion; this occurs by blocking the effects of acetylcholine
at muscarinic cholinergic receptors that mediate the effects of parasympathetic
impulses, thus inhibiting vagal influences on the heart, relaxing the GI and
GU tracts, inhibiting gastric secretions, relaxing the pupil of the eye (mydriatic
effect), and preventing accommodation for near vision (cycloplegic effect).
Peripheral Nervous System Agents ◆ 9
◆ Anticholinergic Agents (continued)
Generic Name Trade Name
Major side effects: Pupil dilation, photophobia, blurred vision, headache, drowsiness, dizziness,
dry mouth, urinary hesitancy, and nasal congestion
Treatment: Prevention of motion sickness (transdermal); preoperatively to produce
amnesia and decrease salivation and excessive respiratory
secretions
Nursing implications: Educate the patient to take the drug as prescribed 30–60 minutes before meals
and avoid excessive dosage; avoid alcohol because serious sedation could
occur; the patient may experience heat intolerance and dangerous reactions
may occur.
Trihexyphenidyl Apo-Trihex (Canada)
Desired effect: Diminished signs and symptoms of parkinsonian syndrome (tremors and rigidity)
Side effects: Dizziness, nervousness, blurred vision, dry mouth, constipation, and
urinary retention
Treatment: Adjunct in the management of parkinsonian syndrome due to many causes,
including drug-induced parkinsonism
CHOLINESTERASE INHIBITORS� Cholinesterase inhibitors are drugs that prevent the degradation of acetylcholine by
cholinesterase.� Neostigmine typifies the reversible cholinesterase inhibitors and serves as a proto-
type for the group.
◆ Cholinesterase Inhibitors
Generic Name Trade Name
Pyridostigmine bromide MestinonDesired effect: Improved muscular function in clients with myasthenia gravis and improved
bladder emptying in clients with urinary retention
Major side effects: Excessive secretions, bronchospasm, bradycardia, abdominal cramps, diarrhea,
excessive salivation, and sweating
Treatment: Used to increase muscle strength in symptomatic treatment of myasthenia gravis;
prevention and treatment of postoperative bladder distention and urinary
retention or ileus
(continued)
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◆ Cholinesterase Inhibitors (continued)
Generic Name Trade Name
Neostigmine ProstigminDesired effect: Increases the concentration of acetylcholine at the sites of cholinergic
transmission, and prolongs and exaggerates the effect of acetylcholine by
reversible inhibiting of the enzyme acetylcholinesterase, causing
parasympathomimetic effects and facilitating transmission at the skeletal
neuromuscular junction; also has direct cholinomimetic activity on neurons in
the autonomic ganglia and the CNS
Major side effects: Seizures, dysarthria, drowsiness, cardiac arrhythmias, thrombophlebitis,
laryngospasm, bronchospasm, urinary frequency, and incontinence
Treatment: Prevention and treatment of postoperative distention and urinary retention;
symptomatic control of myasthenia gravis; diagnosis of myasthenia gravis;
antidote for nondepolarizing junction blockers (e.g., tubocurarine) after
surgery
Nursing implications: Educate the patient to take the drug exactly as prescribed; significant others
should receive extensive education about the effects of the drug, the signs
and symptoms of myasthenia gravis, the fact that muscle weakness may be
related to both drug overdose and to exacerbation of the disease, and that it
is important to report muscle weakness promptly to the nurse or physician so
that proper evaluation can be made.
ADRENERGIC AGENTS (SYMPATHETIC NERVOUS SYSTEM)� Adrenergic agonists are drugs that produce their effects by causing activation of
adrenergic receptors.� Since the sympathetic nervous system acts through those same receptors, responses
to adrenergic agonists and to stimulation by the sympathetic nervous system arevery similar.
� Adrenergic agonists have a broad spectrum of clinical applications, ranging fromtreatment of heart failure to relief of asthma to delay of preterm labor.
� Adrenergic agonists fall into three major chemical classes: naturally occurringcatecholamines, synthetic catecholamines, and noncatecholamines.
There are several different types of adrenergic receptors.
1. Alpha-1 receptors are located in peripheral blood vessels, sex organs, and radialmuscle of the iris in the eye.
a. Activation of alpha-1 receptors in the eye produces mydriasis (dilation of thepupil).
b. Activation of alpha-1 receptors in blood vessels produces vasoconstriction.
c. Activation of alpha-1 receptors in the penis causes ejaculation.
Peripheral Nervous System Agents ◆ 11
2. Alpha-2 receptors are located in the peripheral blood vessels; however, the abilityto activate alpha-2 receptors has only minimal clinical significance.
3. Beta-1 receptors are located in the heart and the kidney. Cardiac beta-1 receptorshave great therapeutic significance.
a. Activation of beta-1 receptors increases heart rate; force of contraction (in-otropic effect) and speed impulse conduction is controlled through the atri-oventricular (A-V) node.
b. Activation of beta-1 receptors in the kidney causes release of renin into theblood, causing peripheral vasoconstriction.
4. Beta-2 receptors are located in the lungs, uterus, and liver.
a. Activation of beta-2 receptors in the uterus causes relaxation of uterine smoothmuscle.
◆ Naturally Occurring Catecholamines
Drug Receptors
Dopamine Dopaminergic, beta-1, and alpha-1
Norepinephrine Alpha-1, alpha-2, and beta-1
Epinephrine Beta-1, beta-2, alpha-1, and alpha-2
b. Activation of beta-2 in arterioles of the lungs causes bronchiolar vasodilation.
c. Activation of beta-2 receptors in the liver promotes glycogenolysis (breakdownof glycogen into glucose), thereby increasing blood levels of glucose. Thenoteworthy adverse response to beta-2 activation is hyperglycemia (elevationof blood glucose).
d. Beta-2 receptors are not present in the heart.
5. Dopamine is the only drug available that can activate dopamine receptors.
a. The degree of receptor specificity displayed by dopamine is dose dependent.When administered in low therapeutic doses, dopamine acts on dopamine re-ceptors only.
b. At low doses (1–2 �g/kg per minute) dopamine dilates renal mesenteric bloodvessels, producing an increase in urinary output.
c. At moderate to large doses (2–10 �g/kg per minute) dopamine activates beta-2receptors in addition to dopamine receptors, increasing cardiac output.
d. In very high doses (10 �g/kg per minute), dopamine activates alpha-1, beta-1,and dopamine receptors, causing vasoconstriction; therefore, it is used in highdoses to treat hypotension (shock) because in such doses it will increase bloodpressure.
Catecholamines (dopamine, norepinephrine, and epinephrine) are synthesized,stored, and metabolized in the brain.
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SYNTHETIC CATECHOLAMINES
1. Synthetic catecholamines include albuterol (Proventil and Ventolin), isoetharine(Bronkosol), metaproterenol (Alupent), and terbutaline (Brethine).
a. All of these drugs selectively activate beta-2 receptors in the lungs and are usedas bronchodilators.
b. Isoproterenol (Isuprel, also a synthetic catecholamine) activates beta-1 andbeta-2 receptors. The desired effect is bronchodilation and management ofventricular arrhythmias due to A-V block.
c. Dobutamine (Dobutrex) is also a synthetic catecholamine. Dobutrex activatesbeta-1 receptors, increasing coronary blood flow and heart rate by acting onbeta-1 receptors in the heart. The primary indication for the drug is heartfailure.
◆ Beta-Adrenergic Agents (Drugs that Act Like Epinephrine)
Generic Name Trade Name
Albuterol Proventil, Ventolin(synthetic catecholamine,
beta activity)
Desired effect: Bronchodilation and increased blood flow to the heart; causes
peripheral vascular constriction because beta-2 receptors are
activated
Major side effects: Nervousness, restlessness, tachycardia, dry mouth, and hyperglycemia
Treatment: Used as a bronchodilator in reversible airway obstruction due to
asthma or chronic obstructive pulmonary disease (COPD)
Dobutamine Dobutrex(synthetic catecholamine,
beta activity)
Desired effects: Increases force of myocardial contractions (inotropic effect), thereby
increasing cardiac output without significantly increasing heart rate
Major side effects: Tachycardia, hypertension, and premature ventricular contractions
Treatment: Short-term management of heart failure due to depressed contractility
from organic heart disease or surgical procedures
Dopamine No commonly used trade name
(catecholamine; dopamine
and beta-1 activity)
Desired effect and Dopamine use is dose-dependent:
nursing implication: 1. Increases blood pressure when given in large doses.
2. In moderate doses, dopamine increases myocardial contractility
(inotropic effect) and cardiac rate, resulting in increased cardiac
output.
3. It improves renal blood flow when administered in low doses.
Peripheral Nervous System Agents ◆ 13
◆ Beta-Adrenergic Agents (Drugs that Act Like Epinephrine)(continued)
Generic Name Trade Name
Major side effects: Hypertension, tachycardia, and headache
Treatment: Hypotension; decreased cardiac output; shock unresponsive to fluid
replacement
Isoetharine BronkosolDesired effect: Bronchodilation
Major side effects: Nervousness, restlessness, tremor, headache, tachycardia, and dry
mouth
Treatment: Used as a bronchodilator in reversible airway obstruction due to
asthma or COPD
Isoproterenol Isuprel(synthetic catecholamine,
beta activity and
vasoconstriction [parenteral])
Desired effect: Bronchodilation; increased heart rate; increased cardiac output
Major side effects: Nervousness, restlessness, tremor, headache, arrhythmias, and
hypertension
Treatment: Used as a bronchodilator in reversible airway obstruction due to
COPD (inhaled); management of ventricular arrhythmias due to
A-V blocks (parenteral); treatment of shock associated with
decreased cardiac output and vasoconstriction (parenteral)
Note: This drug is not used very much any more because of severe side effects.
Metaproterenol Alupent(synthetic catecholamine,
beta activity)
Desired effect: Bronchodilation
Major side effects: Nervousness, restlessness, tremors, hypertension, and hyperglycemia
Treatment: Used as a bronchodilator in reversible airway obstruction due to
COPD
Terbutaline Brethine(synthetic catecholamine,
beta activity)
Desired effect: Bronchodilation
Major side effects: Nervousness, restlessness, tremors, hypertension, and pulmonary
edema
Treatment: Used as a bronchodilator in reversible airway obstruction due to
COPD
Note: The beta-adrenergic agonists are used for bronchodilation or to increase cardiac output and they have common side
effects.
14 ◆ Chapter 2
◆ Alpha- and Beta-Adrenergic Agents
Generic Name Trade Name
Ephedrine No trade name
(synthetic catecholamine,
alpha and beta activity)
Desired effects: Effects mediated by these receptors include vasoconstriction (increased
BP and decreased nasal congestion via alpha receptors), cardiac
stimulation (via beta-1 receptors), and bronchodilation (via beta-2
receptors)
Major side effects: Fear, anxiety, tenseness, dizziness, nervousness, vertigo, rebound
congestion (with nasal use), arrhythmias, decreased urine formation
dysuria, and rapid development of tolerance
Treatment: Used as a bronchodilator in management of reversible airway obstruction;
relief of nasal congestion in viral upper respiratory tract infections or
allergic rhinitis
Nursing implications: Protect solution from light; give only if clear; discard any unused portion;
monitor urine output with parenteral administration; initially urine
formation may be constricted and urine formation decreased; do not
use as a nasal decongestant for longer than 2–5 days.
Epinephrine(adrenaline)
Bronkaid
(naturally occurring
catecholamine with beta-1,
beta-2, and alpha-1 activity)
Desired effect: Bronchodilation; increases rate and force of cardiac contractions and
peripheral vasoconstriction; decreased formation of aqueous humor
and increased aqueous outflow
Side effects: Nervousness, restlessness, insomnia, tremor, headache, arrhythmias, and
hyperglycemia
Treatment: Use IV in ventricular arrest after other measures have failed to restore
circulation; should be given only by trained personnel via intracardiac
puncture and intramyocardial injection; treatment and prophylaxis for
cardiac arrest and attacks of transitory A-V heart block with syncopal
seizures; injection used for relief of respiratory distress due to bronchial
asthma, chronic bronchitis, and emphysema; used as a bronchodilator
in the symptomatic treatment of asthma and hypotension because it can
activate alpha-1 receptors, causing vasoconstriction; use in cardiac arrest
(IV and intracardiac) as an adjunct in the localization of anesthesia
Nursing implications: Use with extreme caution when calculating and preparing; epinephrine is a
very potent drug; small errors in dosage can cause serious adverse
effects; double-check pediatric dosage; protect drug solution from light,
extreme heat, and freezing; do not use pink or brown solution; shake
the suspension for injection well before withdrawing the dose; rotate
subcutaneous injections to prevent necrosis.
Peripheral Nervous System Agents ◆ 15
◆ Alpha- and Beta-Adrenergic Agents (continued)
Generic Name Trade Name
Norepinephrine Levophed(naturally occurring
catecholamine, alpha-1,
alpha-2, and beta-1 activity)
Desired effect: Increased blood pressure; increased cardiac output
Major side effects: Dizziness, somnolence, headache, hallucinations, cardiac arrest, cardiac
arrhythmias, impotence, diarrhea, hepatitis, and pancreatitis
Treatment: Restoration of BP to control certain acute hypotensive states
(pheochromocytomectomies, septicemia, drug reaction, and adjunct
in the treatment of cardiac arrest and profound hypotension
Phenylephrine Neo-Synephrine(synthetic catecholamine,
parenteral, alpha activity,
vasopressor, decongestant)
Desired effect: Powerful postsynaptic alpha-adrenergic agent; receptor stimulant that
causes vasoconstriction and increased systolic and diastolic BP with
little effect on the beta receptors of the heart
Major side effects: Weakness, dizziness, restlessness, anxiety, dries nasal mucosa,
arrhythmias, acute prolonged hypotensive episodes, tachycardia, and
bradycardia
Treatment: Treatment of vascular failure in shock, and as an adjunct for the treatment
of shock to correct hypotension that may persist after adequate fluid
replacement; when administered parenterally it is used to prolong
spinal anesthesia (can also be administered SC, IM, and IV).
Metaraminol Aramine(synthetic catecholamine,
alpha and beta activity)
Desired effects: Maintenance of blood pressure and perfusion of vital organs
Side effects: Apprehension, anxiety, restlessness, dizziness, and arrhythmias
Treatment: Management of hypotension and circulatory shock unresponsive to fluid
volume replacement, which may occur as a consequence of
hemorrhage, drug reaction, or anesthesia
ADRENERGIC ANTAGONISTS (ALPHA ANDBETA BLOCKERS)
� Adrenergic antagonists cause direct blockade of adrenergic receptors.� Adrenergic antagonists display a high degree of receptor specificity. Because of
this specificity, the adrenergic blocking agents can be neatly divided into two major
16 ◆ Chapter 2
groups: alpha-adrenergic blocking agents (drugs that produce selective blockadeof alpha-adrenergic receptors), and beta-adrenergic agents (drugs that produce se-lective blockade of beta receptors).
� Remember it is much easier to understand responses to alpha or beta blockers ifyou first know the response to activation of adrenergic receptors.
� If you have not yet mastered (memorized) alpha and beta responses, you should doso now (or at least keep this information close at hand as you proceed).
◆ Beta-Adrenergic Blockers
Generic Name Trade Name
Acebutolol Sectral (beta-1)
Atenolol Tenormin (beta-1)
Betaxolol Betoptic (beta-1)
Carteolol HCl Cartrol (beta-1 and beta-2)
Metoprolol Lopressor, Toprol-XL (beta-1)
Penbutolol Levatol (beta-1)
Bisoprolol fumarate Zebeta (beta-1)
Nadolol Corgard (beta-1 and beta-2)
Pindolol Visken (beta-1 and beta-2)
Propranolol Inderal, Inderal LA (beta-1 and beta-2)
Sotalol HCl Betapace (beta-1 and beta-2)
Timolol Timoptic, Blocadren (beta-1 and beta-2)
Terazosin Hytrin (alpha-1)
Desired effects: Beta-adrenergic blockers are antianginal, antiarrhythmic, and antihypertensive;
they decrease the influence of the sympathetic nervous system on these tissues,
the excitability of the heart, cardiac workload, oxygen consumption, and the
release of renin, and thus they lower blood pressure.
Major side effects: Bradycardia, tachycardia, fatigue due to CHF, bronchospasm, and hypotension;
impotence and decreased libido
Treatment: Hypertension, cardiac dysrhythmias, angina pectoris, and myocardial infarction
Desired effects: Slows A-V conduction, decreases cardiac rate and oxygen consumption, and
causes vasodilation
Nursing implications: Do not stop these drugs abruptly after long-term therapy; taper drug gradually
over 2 weeks with monitoring; give drug orally with food to facilitate absorption;
beta-blockers cannot be discontinued abruptly, and to do so can cause
life-threatening arrhythmias and hypertension.
Note: For beta-1 blockers: Take apical pulse rate before administration.
For beta-2 blockers: Take blood pressure before administration.
Peripheral Nervous System Agents ◆ 17
◆ Beta-Adrenergic Blockers (continued)
Generic Name Trade Name
Contraindications 1. Beta-1 blockers—bradycardia
2. Beta-2 blockers—bronchospasm (COPD) and hypotension
3. Alpha-1 blockers—hypotension
Other: Timolol and betaxolol are also used to treat glaucoma; Hytrin is also used to
relieve symptoms of an enlarged prostate gland.
Note: The heart has beta-1 receptors and alpha-1 receptors; the lungs have beta-2 receptors; peripheral blood vessels have
alpha-1 and beta-2 receptors.
◆ Beta- and Alpha-Adrenergic Blockers
Generic Name Trade Name
Carvedilol Coreg (alpha-1 and beta-2)
Labetalol Normodyne, Trandate (alpha-1 and beta-2)
Desired effects with
nursing implications:
Produces decreases in BP; alpha- and beta-adrenergic inhibition increases PR
and QT intervals, decreases sinus rate, and decreases peripheral vascular
resistance; also, with alpha and beta blockade elevated plasma renins are
reduced; assess apical and radial pulses before administration and notify
physician of any significant changes; baseline parameters of renal and liver
function are needed before therapy begins.
Side effects: Dizziness, fatigue, weakness, insomnia, ataxia, hyperesthesia, paresthesia,
vertigo, depression; bradycardia, postural hypotension, dependent edema,
peripheral edema, A-V block, hypertension or hypotension, palpitations,
peripheral ischemia, CHF, pulmonary edema
Treatment: Mild to moderate hypertension; treatment of severe hypertension (IV); severe
ventricular tachycardia, supraventricular tachycardia, atrial fibrillation,
ventricular fibrillation not controlled by first-line agents, cardiac arrest
Nursing implications: Alpha and beta blockers cannot be discontinued abruptly; to do so can cause
life-threatening arrhythmias and hypertension.
◆ Alpha-Adrenergic Blockers
Generic Name Trade Name
Clonidine CatapresAlfuzosin UroxatralPrazosin MinipressTerazosin HytrinPhentolamine Rogitine
(continued)
18 ◆ Chapter 2
◆ Alpha-Adrenergic Blockers (continued)
Generic Name Trade Name
Doxazosin CarduraTamsulosin FlomaxDesired effects: Reduce total peripheral resistance through alpha blockade; do not affect cardiac
output or heart rate; lower blood pressure and decrease cardiac preload
(diastolic) and afterload (systolic); blood pressure must be taken before
administration of alpha-adrenergic blockers.
Side effects: Dizziness, fatigue, weakness, insomnia, ataxia, hyperesthesia, paresthesia, vertigo,
depression; bradycardia, postural hypotension, dependent edema, peripheral
edema, A-V block, hypertension, palpitations, peripheral ischemia, CHF,
pulmonary edema
Treatment: Hypertension, used alone or as part of combination therapy
Note: Rogitine is used to treat hypertension associated with pheochromocytoma or other adrenergic excess, such as administration
of phenylephrine or consumption of tyramine-containing foods in clients using MAOI therapy.
◆ Sympatholytic Central-Acting Alpha-Adrenergic Inhibitors
These central-acting antiadrenergic agents are drugs that act within the CNS to reduce the firing
of sympathetic neurons.
Generic Name Trade Name
Clonidine CatapresMethyldopa AldometGuanabenz WytensinDesired effect: Competitively block postsynaptic alpha-1 receptors, decreasing sympathetic tone
of the vascular system, dilating blood vessels and thus lowering arterial BP
Major side effects: Drowsiness, sedation, orthostatic hypotension, weakness, dizziness, tachycardia,
bradycardia, arrhythmias, CHF, angina, dry mouth, constipation
Treatment: Hypertension used alone or as part of combination therapy; used to reduce
blood pressure in situations in which hypertension is due to adrenergic excess
by decreasing sympathetic outflow, such as pheochromocytoma
Note: These are no longer used to treat essential hypertension because they also block presynaptic alpha-2 receptors that are
believed to mediate a feedback inhibition of further norepinephrine release; this accentuates the reflex tachycardia caused by
the lowering of BP.
◆ Adrenergic Neuron Blockers
Generic Name Trade Name
Adrenergic neuron blocking agents are drugs that act presynaptically to reduce the release of norepinephrine
from sympathetic neurons.
Guanethidine monosulfate Ismelin
Peripheral Nervous System Agents ◆ 19
◆ Adrenergic Neuron Blockers (continued)
Generic Name Trade Name
Reserpine No commonly used trade name
Guanadrel sulfate HylorelDesired effect: Reduce blood pressure
Side effects: Hypotension, bradycardia, nasal congestion
Treatment: Hypertension
Nursing implications: Reserpine can produce severe depression that may persist for months after
the drug is withdrawn.
Ismelin may cause impotence, nocturia, urinary incontinence, and inhibition
of ejaculation.
Hylorel may cause fatigue, faintness, drowsiness, visual disturbances,
paresthesias, confusion, and psychological problems.
◆ Angiotensin II Receptor Blockers
Generic Name Trade Name
Candesartan AtacandLosartan CozaarIrbesartan AvaproTelmisartan MicardisValsartan DiovanOlmesartan BenicarEprosartan TevetenTreatment: Hypertension, alone or in combination with other antihypertensive agents,
particularly diuretics and calcium channel blockers
Desired effects: Blocks the vasoconstrictor and aldosterone-producing effects of angiotensin II at
various receptor sites, including vascular smooth muscle cells and the adrenal
glands
Therapeutic effect: Lowering of blood pressure
Side effects: Headache, dizziness, syncope, muscle weakness, hypotension, fever, gout, rash,
inflammation, urticaria, pruritus, alopecia, dry skin, diarrhea, abdominal pain,
nausea, constipation, dry mouth, dental pain
Nursing implications: Administer without regard to meals; ensure that the patient is not pregnant
before beginning therapy; suggest the use of barrier birth control while using
olmesartan (Benicar); fetal injury and deaths have been reported; find an
alternate method of feeding the infant if given to a nursing mother; depression
of the renin-angiotensin system in infants is potentially very dangerous; alert the
surgeon and mark the patient’s charts with a notice that olmesartan (Benicar) is
being taken; blockade of the renin-angiotensin system following surgery can
produce problems; hypotension may be reversed with volume expansion
Chapter
3 Central Nervous SystemAgents
DRUGS FOR PARKINSON’S DISEASE
NURSING IMPLICATIONS
1. Parkinson’s disease is a neurological disorder characterized by disturbance ofmovement. In Parkinson’s disease, there is an imbalance between dopamine andacetylcholine.
2. Dopamine is an inhibitory transmitter in the brain. Acetylcholine is an excitatorytransmitter.
3. By suppressing discharge of the cholinergic neurons, the dopaminergic neuronscan prevent excessive excitation.
4. Movements are normal when the excitatory effects of acetylcholine are balancedby the inhibitory influence of dopamine.
5. Movement disorders similar to those of Parkinson’s disease can occur as sideeffects of therapy with antipsychotic agents.
6. These dyskinesias, which are referred to as extrapyramidal side effects, result fromthe blockade of dopamine receptors in the striatum.
20
Central Nervous System Agents ◆ 21
7. Sinemet (carbidopa/levodopa) is the drug of choice for treating Parkinson’sdisease.1
8. Full therapeutic response may take several months to develop. The client shouldbe informed that beneficial effects are likely to increase steadily over the first fewmonths.
9. In contrast to the dramatic improvement seen during initial therapy, long-termtherapy with Sinemet has been disappointing. Although symptoms may be wellcontrolled during the first 2 years of treatment, by the end of 5 years, the client’sability to function may deteriorate to pretreatment levels.
◆ Drugs for Parkinson’s Disease
Generic Name Trade Name
Carbidopa/levodopa SinemetLevodopa No commonly used trade name
Carbidopa No commonly used trade name
Tolcapone No commonly used trade name
Desired effect: Unlike dopamine, levodopa penetrates the blood–brain barrier; it
relieves the symptoms of parkinsonism but not drug-induced
extrapyramidal disorders.
Major side effects: Urinary retention, urinary incontinence, involuntary movements,
increased hand tremors, weakness, agitation, anxiety, psychiatric
problems, insomnia, nightmares, orthostatic hypotension,
tachycardia, hypertension, and alopecia
Treatment: Treatment of parkinsonian syndrome; not useful for drug-induced
extrapyramidal reactions.
Nursing implications: Arrange to decrease dosage if therapy is interrupted; observe for the
development of suicidal tendencies; give with meals if GI upset
occurs; ensure that the patient voids before receiving a dose if
urinary retention is a problem.
Notes: Administer only after an MAOI has been discontinued for 2 weeks. If previously on levodopa, discontinue for at least
8 hours before changing to Sinemet. Tolcapone is typically administered with levodopa, prolonging the effects of the latter
drug and reducing the overall quantity of medications a client must take. The two together provide more consistent control of
movement and speech.
1 Having no therapeutic effects of its own, carbidopa is almost always administered with levodopa in a
single formulation containing both drugs. Available as tablets or sustained-release capsules, this combi-
nation is marketed under the trade name Sinemet. Levodopa has therapeutic effects when administered
alone and may be prescribed.
22 ◆ Chapter 3
◆ Anticholinergic Antiparkinsonism Agents
Generic Name Trade Name
Amantadine SymmetralBenztropine CogentinBromocriptine ParlodelTrihexyphenidyl Apo-Trihex (Canada)
Pergolide mesylate PermaxEntacapone ComtanDesired effect: Relief of tremors and rigidity in parkinsonian syndrome
Major side effects: Dizziness, nervousness, blurred vision, mydriasis (dilation of pupils),
dry mouth, and constipation
Treatment: Parkinson’s disease (Cogentin, Apo-Trihex, and diphenhydramine can
also be used to decrease the side effects of antipsychotic drugs
[e.g., Haldol].)
Nursing implications: Drug-induced parkinsonism is a parkinsonlike disease induced by use of
antipsychotic drugs and characterized by bradykinesia masklike face,
drooling, tremors, pill-rolling motions, rigidity, shuffling gait, stooped
posture, dyskinesia, sedation, blurred vision, nausea, vomiting,
headache, photosensitivity, constipation, hypotension, urinary
retention, impotence, breast engorgement and sometimes lactation
in both women and men, amenorrhea, and glaucoma
◆ Antiseizure Agents
Generic Name Trade Name
Phenobarbital No commonly used trade name
(PO, IV, and IM)
Phenytoinsodium
Dilantin (can also be used to treat digitalis-induced dysrhythmias;
Dilantin can only be mixed with normal saline.)
Carbamazepine TegretolDiazepam ValiumGabapentin NeurontinValproic acid DepakeneDivalproex DepakoteTreatment: Seizures
Desired effect: Diminished seizure activity
Central Nervous System Agents ◆ 23
◆ Antiseizure Agents (continued)
Generic Name Trade Name
Major side effects
with nursing
implications:
Tegretol: drowsiness, ataxia, bone marrow suppression, aplastic anemia
Dilantin: gingival hyperplasia; pink, red, or reddish-brown discoloration of
urine; male sexual dysfunction
Depakene: hepatotoxicity, prolonged bleeding; may potentiate the effects
of warfarin (Coumadin)
Depakote may cause a life-threatening pancreatitis, hepatic failure,
depression, psychosis, aggression, hyperactivity, behavioral
deterioration, and weakness.
Nursing implications: Confusion has occurred between the use of delayed-release
Depakote and Depakote ER; dosing of the two agents is very different and
serious adverse effects can occur, so use extreme caution; Dilantin and
Valium cannot be mixed with other drugs; antiseizure drugs may also be
used as mood stabilizers.
Notes: Tegretol can only be administered by mouth. Tegretol is also used for manic-depressive illness, schizoaffective illness,
alcohol withdrawal, and its antidiuretic effect in diabetics.
DRUGS USED TO TREAT SPASTICITY� The term spasticity refers to a group of movement disorders of CNS origin.� These disorders are characterized by heightened muscle tone, spasm, and loss of
dexterity.� The most common causes of spasticity are multiple sclerosis and cerebral palsy.� Other causes include traumatic spinal cord lesions and stroke.� Spasticity is managed with a combination of drugs and physical therapy.
◆ Drugs Used to Treat Spasticity
Generic Name Trade Name
Baclofen LioresalDantrolene DantriumDiazepam ValiumDesired effect: Act directly on muscles to cause reduction of muscle spasticity
Major side effects: Dizziness, drowsiness, lethargy, hypotension, fatigue
Treatment: Spasticity
24 ◆ Chapter 3
PSYCHOTHERAPEUTIC AGENTS
◆ Antipsychotic Agents Used to Treat Schizophrenia
Generic Name Trade Name
Chlorpromazine Thorazine (discolors urine pink to reddish-brown)
Clozapine ClozarilFluphenazine ProlixinHaloperidol HaldolLoxapine LoxitaneMolindone MobanMesoridazine SerentilThioridazine MellarilThiothixene NavanePerphenazine TrilafonRisperidone RisperdalOlanzapine ZyprexaQuetiapine SeroquelDesired effect: Schizophrenia is the most common indication for antipsychotic drugs;
they suppress symptoms during acute psychotic episodes and, when
taken chronically, can greatly decrease the risk of relapse; initial
antidepressant effects are seen in 1–2 days, but full effects develop
gradually over 6–8 weeks.
Major side effects: One of the many side effects these drugs can produce is the
extrapyramidal reaction, especially dyskinesia (slow, rhythmic,
automatic stereotyped movements, either generalized or in single
muscle groups).
Treatment: They are used to treat acute and chronic psychosis and for sedation
(the most common psychosis is schizophrenia).
Symptoms developing within the first month of therapy are
indistinguishable from those of idiopathic Parkinson’s disease.
Because of these neurological side effects, the traditional antipsychotics
are known alternatively as neuroleptics.
Extrapyramidal reactions (pseudoparkinsonism) are treated with
antiparkinsonian drugs such as Cogentin or Artane; they must be
gradually discontinued over a 3-month period.
When these medications are administered IM, symptoms are usually
controlled within 48–70 hours, and then oral medications can be
given.
Nursing implications: Monitor the elderly for dehydration, and institute remedial measures
promptly; sedation and decreased thirst related to CNS effects can
lead to dehydration.
Central Nervous System Agents ◆ 25
◆ Antipsychotic Agents Used toTreat Schizophrenia (continued)
Generic Name Trade Name
Educate the patient and family about the need for blood tests weekly or
once a month as ordered by the physician; the dosage may be
increased gradually to achieve the most effective dose; tell the
patient to not take more than the prescribed dosage; do not make
up a missed dose, instead contact a heath care provider; do not
stop taking these drugs suddenly; gradual reduction of dosage is
needed to prevent side effects; educate the patient and family about
the side effects of the drug (e.g., drowsiness, seizure, dizziness,
syncope, headache, tremor, and agitation).
ANTIDEPRESSANTS
These agents fall into the following four major groups:
1. Tricyclic antidepressants
2. Monoamine oxidase inhibitors (MAOIs)
3. Selective serotonin reuptake inhibitors (SSRIs)
4. Miscellaneous antidepressants
TRICYCLIC ANTIDEPRESSANTS
The tricyclic antidepressants are drugs of first choice for many clients with majordepression.
◆ Tricyclic Antidepressants
Generic Name Trade Name
Amitriptyline
(onset 2–3 weeks)
Elavil
Imipramine
(onset 1 hour)
Tofranil
Amoxapine AsendinDesipramine NorpraminDoxepin Triadapin (Canada), Zonalon (Canada)
(continued)
26 ◆ Chapter 3
◆ Tricyclic Antidepressants (continued)
Generic Name Trade Name
Nortriptyline Pamelor, AventylProtriptyline Triptil (Canada), VivactilDesired effects: Relief of symptoms of depression
Side effects: Sedation and anticholinergic (atropinelike) effects (dry mouth, blurred
vision, increased intraocular pressure), confusion (especially in the
elderly), disturbed concentration, hallucinations, disorientation,
anxiety, nervousness, restlessness, agitation, panic, insomnia,
nightmares, orthostatic hypotension or hypertension, syncope,
tachycardia, MI, arrhythmias, heart block; hematologic: bone marrow
depression, including thrombocytopenia and leukopenia
Treatment: Relief of symptoms of depression (endogenous depression is most
responsive); sedative effects may help depression associated with
anxiety and sleep disturbance
Desired effects: Alleviate mood, increase activity and alertness, decrease morbid
preoccupation, improve appetite, and normalize sleep patterns
Nursing implications: Drug should not be administered to patients with a history of
hypersensitivity to any tricyclic drug, recent MI, myelography within
the previous 24 hours or scheduled within 48 hours, pregnancy,
lactation, preexisting cerebrovascular disorders, angle-closure
glaucoma, increased intraocular pressure, urinary retention, seizure
disorders, hyperthyroidism, impaired liver or renal function,
psychiatric patients; limit drug access to depressed and potentially
suicidal patients.
MONOAMINE OXIDASE INHIBITORS (MAOIS)� The combination of a tricyclic antidepressant (e.g., Elavil, Tofranil) and an MAOI
can lead to severe hypertension due to excessive adrenergic stimulation of the heartand blood vessels. Therefore, combined therapy with tricyclic antidepressants andMAOIs is generally avoided.
◆ Monoamine Oxidase Inhibitors
MAOIs are not used as frequently today because newer drugs with fewer side effects are now available.
Generic Name Trade Name
Isocarboxazid MarplanPhenelzine NardilTranylcypromine Parnate
Central Nervous System Agents ◆ 27
◆ Monoamine Oxidase Inhibitors (continued)
Generic Name Trade Name
Desired effect: Relief of depression
Major side effects: Orthostatic hypotension, hypertensive crisis from dietary tyramine; avoid foods
that contain tyramine, a substance that promotes the release of
norepinephrine from sympathetic nerves; tyramine is found in practically all
cheeses, avocados, figs, dried or smoked fish, brewer’s yeast extracts, beer,
wine, pickled herring, and chicken liver.
Treatment: MAOIs are second- or third-line antidepressants for most clients.
Although these drugs are as effective as the tricyclics, they are more dangerous.
Nursing implications: Antidepressant effect starts at 1–4 weeks and peaks at 3–4 weeks.
Monitor BP and orthostatic BP carefully; arrange for a more gradual increase in
dosage initially in patients who show a tendency toward hypotension.
Arrange for periodic liver function tests during therapy; discontinue drug at
the first sign of hepatic dysfunction or jaundice.
SELECTIVE SEROTONIN REUPTAKE INHIBITORS (SSRIS)� These drugs produce selective blockade of serotonin reuptake.� These drugs are as effective as the tricyclic antidepressants and appear to be safer,
although possible long-term effects are not yet known.
◆ Selective Serotonin Reuptake Inhibitors
Generic Name Trade Name
Paroxetine PaxilFluoxetine ProzacSertraline ZoloftTrazodone DesyrelEscitalopram LexaproDesired effect: Relief of depression
Side effects: SSRIs should not be combined with MAOIs since severe adverse effects have
been reported. MAOIs should be withdrawn at least 14 days before
beginning to take SSRIs. Clients should be instructed that SSRIs and MAOIs
take about 4 weeks to produce a steady-state plasma drug level. Side effects
include insomnia, sexual dysfunction, nervousness, weight loss, painful
menstruation, and anxiety.
Treatment: Major depression; most effective in patients with major depressive disorder;
obsessive-compulsive disorder, posttraumatic stress disorder, social anxiety,
generalized anxiety disorder, panic disorder
28 ◆ Chapter 3
◆ Miscellaneous Antidepressants
Generic Name Trade Name
Amoxapine AsendinBupropion Wellbutrin, ZybanMaprotiline LudiomilDesired effect: Relief of depression that will occur slowly over several weeks
Major side effects: Drowsiness, sedation, lethargy, dry mouth, dry eyes, blurred vision, and
hypotension; Asendin may cause extrapyramidal reactions or tardive
dyskinesia. Wellbutrin and Ludiomil may cause seizures.
Treatment: Treatment of depression and anxiety associated with depression; aid to smoking
cessation (Zyban)
Nursing implications: Take drug in equally divided doses three to four times a day as prescribed for
depression. Avoid or limit the use of alcohol while on this drug; seizures can
occur if these are combined. May be used with transdermal nicotine; most
effective for smoking cessation if combined with behavioral support program
BIPOLAR DISORDER
Bipolar disorder is mania and depression separated by periods in which mood is normal.The mainstay of therapy is lithium.
NURSING IMPLICATIONS OF LITHIUM THERAPY� It is important that sodium levels remain normal. Clients should be instructed to
maintain normal sodium intake; a sodium-free diet cannot be used. Since diureticspromote sodium loss, these agents must be employed with caution. Sodium losssecondary to diarrhea can be sufficient to cause lithium accumulation, and thepatient should be warned of this possibility.
� Measurement of plasma lithium levels is an essential feature of treatment.
DRUG THERAPY FOR BIPOLAR DISORDER
◆ Drugs for Bipolar Disorder
Generic Name Trade Name
Carbamazepine TegretolValproic acid DepakeneLithium No commonly used trade name
Desired effect: Control manic episodes; for many clients, adjunctive therapy with a
benzodiazepine (e.g., diazepam) or an antipsychotic agent can be helpful.
Central Nervous System Agents ◆ 29
◆ Drugs for Bipolar Disorder (continued)
Generic Name Trade Name
Side effects: Adverse effects that occur when lithium levels are excessive include abdominal
bloating, GI upset, diarrhea, muscle weakness, hypotension, slurred speech,
and oliguria. Adverse effects that occur at therapeutic drug levels include
fatigue, muscle weakness, headache, confusion, memory impairment, and
leukocytosis (10,000–18,000 WBCs/mm3). Carbamazepine and valproic
acid side effects and their use in seizure disorder are discussed in the section
on antiseizure agents.
Treatment: Bipolar disorder
Nursing implications: Tell the patient that a complete blood count should be obtained prior to
treatment, and annually or more frequently if so ordered by the health care
provider.
Note: Carbamazepine (Tegretol) and valproic acid (Depakene) were originally developed and marketed to treat seizure
disorders. In recent years lithium has been used with success to treat clients with bipolar disorder. Carbamazepine (Tegretol)
is reserved for clients who fail to respond to lithium or who cannot tolerate lithium’s side effects. Tegretol is also used for
treatment of alcohol withdrawal symptoms.
DRUGS USED TO TREAT ANXIETY AND INSOMNIA
NURSING IMPLICATIONS
1. Anxiety and insomnia are common client complaints, and the drugs employedfor treatment are widely prescribed.
2. Drugs that promote sleep are referred to as hypnotics.
3. The distinction between antianxiety effects and hypnotic effects is frequently amatter of dosage; some drugs relieve anxiety in low dosages and induce sleep inhigh doses.
4. Therefore, a single drug may be considered both an antianxiety agent and ahypnotic agent, depending on the reason for its use and the dosage employed.
5. Some drugs are specifically for insomnia and some are specifically for anxiety.
6. Benzodiazepines are drugs of first choice for treating anxiety and insomnia.
7. In addition, these agents are used to induce general anesthesia and manage seizuredisorders, muscle spasms, panic disorder, and withdrawal from alcohol.
8. The most frequently prescribed benzodiazepines are diazepam (Valium), lo-razepam (Ativan), and alprazolam (Xanax).
9. The popularity of the benzodiazepines as sedatives and hypnotics stem fromtheir clear superiority over the alternatives (barbiturates and other general CNSdepressants).
10. Benzodiazepines are safer than the general CNS depressants and have a lowerpotential for abuse.
30 ◆ Chapter 3
BARBITURATES USED TO TREAT INSOMNIA
NURSING IMPLICATIONS
1. These drugs cause relatively nonselective depression of CNS function and are theprototypes for the general CNS depressants (e.g., Nembutal, Seconal).
2. Because they depress multiple aspects of CNS function, barbiturates can be usedfor daytime sedation, induction of sleep, suppression of seizures, and generalanesthesia.
3. Barbiturates cause tolerance and dependence, have high abuse potential, and aresubject to multiple drug interactions.
4. Because of these undesirable properties, the barbiturates, which were once usedwidely, have been largely replaced by newer and safer drugs, primarily the ben-zodiazepines.
5. However, although their use has declined greatly, barbiturates still have importantapplications in seizure control and anesthesia.
◆ Barbiturates Used to Treat Insomnia
Generic Name Trade Name
Amobarbital AmytalPentobarbital NembutalSecobarbital SeconalAprobarbital AlurateDesired effect: Sedative, hypnotic effect
Treatment of: Insomnia; short term as a preoperative sedative
Side effects: Drowsiness, lethargy, respiratory depression, laryngospasm (spasm of laryngeal
muscles), hangover, hypotension
◆ Benzodiazepines Used to Treat Insomnia
Generic Name Trade Name
Flurazepam DalmaneTemazepam RestorilTriazolam HalcionDesired effect: Relief of insomnia
Side effects: Dizziness, daytime drowsiness, lethargy, hangover, confusion, mental depression,
psychological dependence
Treatment: Insomnia
Central Nervous System Agents ◆ 31
◆ Benzodiazepines Used to Treat Anxiety
Generic Name Trade Name
Zanamivir RelenzaAlprazolam XanaxChlordiazepoxide LibriumDiazepam ValiumLorazepam AtivanMidazolam VersedOxazepam Serax, NovoxapamDesired effect: Sedation and relief of anxiety
Side effects: Dizziness, drowsiness, lethargy, blurred vision, apathy, depression, restlessness
Treatment: Anxiety
Note: Versed is frequently used preoperatively because of its amnestic effect and because it can be combined with many
other preoperative drugs. The sedative/hypnotic drugs listed above cannot be combined with other drugs.
◆ Nonbarbiturate Sedative/Hypnotic Drugs Used toTreat Insomnia
Generic Name Trade Name
Zaleplon SonataQuazepam DoralChloral hydrate No common trade name
Zolpidem AmbienZaleplon SonataDesired effects: Sedative and hypnotic
Major side effects: Headache, depression, drowsiness, somnolence, abnormal vision, lack
of coordination, short-term memory impairment
Treatment: Short-term treatment of insomnia
Nursing implications: Cannot be administered to patients with hypersensitivity to zaleplon
(Sonata), impaired hepatic or respiratory function, pregnancy, labor
or delivery, lactation, depression
• Doral
Desired effects: Sedative and hypnotic effects
Side effects: Transient, mild drowsiness initially; sedation; depression; lethargy;
apathy; fatigue; light-headedness; disorientation; restlessness;
confusion
Nursing implications: Ensure that the patient is not pregnant before use; recommend the use
of barrier contraceptives. Monitor liver and kidney function, and
CBC during long-term therapy.
(continued)
32 ◆ Chapter 3
◆ Nonbarbiturate Sedative/Hypnotic Drugs Used toTreat Insomnia (continued)
Generic Name Trade Name
Treatment: Insomnia characterized by difficulty in falling asleep, frequent nocturnal
awakenings, or early morning awakening; recurring insomnia or poor
sleeping habits; acute or chronic medical situations requiring restful sleep
• Chloral hydrate
Desired effects: Sedative and hypnotic effects
Side effects: Somnambulism (sleep walking), disorientation, incoherence, paranoid
behavior, excitement, delirium, drowsiness, staggering gait, ataxia,
light-headedness, vertigo, nightmares, malaise, mental confusion, headache,
hallucinations
Treatment: Nocturnal sedation; preoperative sedation to lessen anxiety and induce sleep
without depressing respiration or cough reflex
Nursing implications: Use cautiously with impaired liver or kidney function, depression, or suicidal
tendencies
• Ambien
Desired effects: Sedative and hypnotic effects
Side effects: Amnesia, daytime drowsiness, dizziness, “drugged” feeling, diarrhea, nausea,
vomiting, hypersensitivity reactions, physical and psychological dependence
Treatment of: Short-term treatment of insomnia
Nursing implications: Assess mental status and sleep patterns and potential for abuse prior to
administering this medication. Storage in tight container in cool
environment. Teach patients to avoid alcohol ingestion.
Assess for depressant use; serious CNS depression may result.
DRUGS USED TO TREAT PAIN� The term narcotic has had so many definitions, it can no longer be used with any
precision.� The term opiate is more specific and applies only to compounds contained in opium
(e.g., morphine, codeine).
◆ Narcotic Analgesics (Act as Agonists atSpecific Opioid Receptors)
Generic Name Trade Name
Butorphanol StadolHydromorphone Dilaudid
Central Nervous System Agents ◆ 33
◆ Narcotic Analgesics (Act as Agonists atSpecific Opioid Receptors) (continued)
Generic Name Trade Name
Meperidine DemerolMethadone Dolophine, Methadone HCl Intensol, MethadoseCodeine No commonly used trade name
Morphine No trade name
Nalbuphine NubainDesired effects: These narcotic analgesics act at opioid receptors in the CNS to produce
analgesia, euphoria, and sedation; they also act in the medullary cough center
to depress cough reflex.
Side effects: Sedation, confusion, hallucinations, dysphoria, hypotension, urinary retention
Treatment: Moderate to severe pain, sedative prior to surgery
Nursing implications: Morphine is used in management of severe pain, management of pulmonary
edema, and relief of pain associated with myocardial infarction.
Methadone is also used for detoxification and temporary maintenance treatment
of narcotic addiction (it is ineffective for relief of general anxiety).
Morphine is the prototype of the strong opioid analgesics and remains the
standard by which newer opioids are measured.
Morphine and other opioids are subject to abuse, mainly because of their ability
to cause pleasurable experiences (e.g., euphoria and sedation).
◆ Narcotic Antagonist
Generic Name Trade Name
Naloxone NarcanTreatment: Overdose of opioid (narcotic) agents
DRUGS USED TO TREAT HEADACHES� Drug selection depends on the intensity of the attack. For mild to moderate symp-
toms, aspirin, acetaminophen, or ibuprofen may be sufficient.� If this is inadequate, aspirin combined with codeine may be tried.� If these analgesics prove insufficient, an ergot alkaloid (either ergotamine or dihy-
droergotamine) may be used.� If these agents fail to relieve pain, an opioid (narcotic) analgesic (e.g., meperidine
[Demerol]) may be needed.
34 ◆ Chapter 3
◆ Antimigraine Agents
Generic Name Trade Name
Ergotamine No commonly used trade name
Dihydroergotamine No commonly used trade name
Sumatriptan ImitrexValproic acid DepakeneRizatriptan MaxaltNaratriptan AmergeZolmitriptan ZomigEletriptan RelpaxAlmotriptan AxertFrovatriptan FrovaValdecoxib BextraDesired effect: Constriction of dilated carotid artery bed with resolution of vascular
headache
Side effects: Abdominal pain, muscle pain, extremity stiffness, stiff neck, stiff
shoulders, leg weakness, numbness or tingling in fingers or toes
Nursing implications: Contraindicated in peripheral vascular disease, cardiovascular disease,
hypertension, pregnancy
Treatment: Migraine headaches
◆ Drugs Used to Treat Alzheimer’s Disease
Generic Name Trade Name
Galantamine ReminylDonepezil AriceptTacrine CognexRivastigmine Exelon Oral SolutionDesired effects: These drugs are centrally acting reversible cholinesterase inhibitors leading to
elevated acetylcholine levels in the cortex, which slows the neuronal
degradation that occurs in Alzheimer’s disease.
Side effects: Headache, fatigue, dizziness, confusion, ataxia, insomnia, somnolence, tremor,
agitation, depression, anxiety, abnormal thinking
Nursing implications: Name confusion has occurred between Aricept (donepezil) and Aciphex
(rabeprazole); use caution. Name confusion has also occurred between
tacrine and Tequin (gatifloxacin); use caution.
Treatment: Mild to moderate dementia of the Alzheimer’s type
Chapter
4 Drugs that Affect Fluidand Electrolyte Balance
DIURETICS
NURSING IMPLICATIONS
1. Diuretics are drugs that increase the output of urine. These agents have one majorapplication: the mobilization of edematous fluid associated with hypertension,heart failure, cirrhosis, and kidney disease.
2. High-ceiling (loop) diuretics are the most effective diuretics available. These drugsproduce greater loss of fluid and electrolytes than other diuretics because their siteof action is in the loop of Henle.
3. Furosemide (Lasix) is especially useful in patients with severe renal impairment,since unlike the thiazides, this drug can promote diuresis even when renal bloodflow and glomerular filtration rates are low. Thiazides have little or no directeffect on glomerular filtration rate, whereas Lasix exhibits a renal vasodilatoreffect, resulting in less vascular resistance and increased renal blood flow. Lasix istherefore useful in renal failure, although it is contraindicated in anuria (absenceof urine formation).
35
36 ◆ Chapter 4
THIAZIDES
Nursing Implications
Thiazide diuretics (also known as benzothiadiazides) have effects similar to those ofthe loop diuretics. Like the loop diuretics, thiazides increase renal excretion of sodium,chloride, potassium, and water. In addition, thiazides elevate plasma levels of uric acidand glucose. The principal difference between the thiazides and the loop diuretics isthat the maximum diuresis produced by the thiazides is considerably lower than themaximum diuresis produced by the high-ceiling agents.
◆ High-Ceiling (Loop) Diuretics
Generic Name Trade Name
Furosemide LasixEthacrynic acid EdecrinBumetanide BumexDesired effect: Diuresis and subsequent mobilization of excess fluid (edema, pleural
effusion); lower blood pressure
Side effects: Dehydration, hypotension, hypokalemia, hyponatremia, metabolic
alkalosis, hypomagnesemia
Treatment: Pulmonary edema associated with congestive heart failure, edema of
cardiac, hepatic, or renal origin that has been unresponsive to less
effective diuretics
Note: Lasix given IV too rapidly will cause hearing loss.
◆ Thiazides
Generic Name Trade Name
Chlorothiazide DiurilHydrochlorothiazide HydroDIURILHydroflumethiazide Diucardin, SaluronMethyclothiazide EnduronTrichlormethiazide Diurese, Trichlorex (Canada)
Benzthiazide ExnaMetolazone Mykrox, ZaroxolynDesired effect: Lowering of blood pressure in hypertensive patients and diuresis with
subsequent mobilization of edema
Drugs that Affect Fluid and Electrolyte Balance ◆ 37
◆ Thiazides (continued)
Generic Name Trade Name
Side effects: Hypokalemia, hyperuricemia, hypotension, hyperglycemia,
hypochloremia, hyponatremia, hypomagnesemia; metolazone also
has the following side effects: aplastic anemia, hemolytic anemia,
leukopenia, agranulocytosis, neutropenia
Treatment: Alone or in combination with other agents in the management of
mild to moderate hypertension; alone or in combination in the
treatment of edema associated with congestive heart failure,
nephrotic syndrome, or pregnancy
POTASSIUM-SPARING DIURETICS
Nursing Implications
The potassium-sparing diuretics can elicit two potentially useful responses—an increasein urine production and a decrease in potassium excretion. Because their diuretic effectsare limited, the potassium-sparing drugs are employed to counteract potassium losscaused by the loop diuretics and thiazides.
◆ Potassium-Sparing Diuretics
Generic Name Trade Name
Spironolactone AldactoneTriamterene DyreniumAmiloride • Midamos
Desired effects: Competitively blocks the effects of aldosterone in the renal tubule, causing
loss of sodium and water and retention of potassium
Side effects: Dizziness, vertigo, paresthesias, weakness, headache, drowsiness, fatigue,
orthostatic hypotension, volume depletion, polyuria, nocturia,
impotence, loss of libido
Treatment: Used alone or in combination with other diuretics to treat hypertension
and edema caused by any disorder
Nursing implications: They augment diuresis and help counteract the potassium-wasting effect of
the more powerful diuretics (e.g., Lasix, Hydro-DIURIL).
OSMOTIC DIURETICS
Nursing Implications
1. Four compounds, mannitol, urea, glycerin, and isosorbide, are classified as osmoticdiuretics. However, of the four, only mannitol is used for its diuretic actions.
38 ◆ Chapter 4
2. Mannitol differs from other diuretics both in mechanism of action and clinicalapplication.
3. Mannitol promotes diuresis by creating an osmotic force within the lumen of thenephron. Diuresis begins in 30–60 minutes and persists for 6–8 hours.
◆ Osmotic Diuretics
Generic Name Trade Name
Mannitol No commonly used trade name
Urea No commonly used trade name
Glycerin Colace SuppositoriesIsosorbide No commonly used trade name
• Mannitol
Desired effect: Mannitol increases the osmotic pressure of the glomerular filtrate,
thereby inhibiting reabsorption of water and electrolytes; cause
excretion of water, sodium, potassium, chloride, calcium, magnesium
urea, and uric acid
Side effects: Transient volume expansion, tachycardia, chest pain, congestive heart
failure, pulmonary edema, hyponatremia or hypernatremia,
hypokalemia, hypotension, and dehydration; fluid loss in excess of
electrolyte excretion may produce hypernatremia or hyperkalemia.
Treatment: Mannitol is used as an adjunct in the treatment of acute renal failure
before evidence of permanent renal failure is present; adjunct in the
treatment of edema caused by increased intracranial and intraocular
pressure and other disorders; reduction of intracranial or intraocular
pressure
• Urea
Desired effects: Elevates the osmolarity of the glomerular filtrate, hindering the
reabsorption of water and leading to a loss of water, sodium, and
chloride; creates an osmotic gradient in the eye between plasma and
ocular fluids, reducing intraocular pressure, and hypotension
Major side effects: Dizziness, headache, syncope, nausea, vomiting, thrombophlebitis
Treatment: Reduction of intracranial pressure and treatment of cerebral edema, and
reduction of elevated intraocular pressure
• Glycerin
Desired effects: Elevates the osmolarity of the glomerular filtrate, thereby hindering the
reabsorption of water and leading to loss of water, sodium, and
chloride; creates an osmotic gradient in the eye between plasma and
ocular fluids, thereby reducing intraocular pressure; causes the local
absorption of sodium and water in the stool, leading to a more liquid
stool and local intestinal movement.
Major side effects: Cardiac arrhythmias, confusion, headache, syncope, disorientation,
severe dehydration and hypotension
Drugs that Affect Fluid and Electrolyte Balance ◆ 39
◆ Osmotic Diuretics (continued)
Generic Name Trade Name
Treatment: Glaucoma, before ocular surgery is performed under local anesthetic
when a reduction in intraocular pressure is indicated; temporary
constipation, before rectal surgery
• Isosorbide
Desired effects: Elevates the osmolarity of the glomerular filtrate, hindering the reabsorption
of water and leading to a loss of water, sodium, and chloride; creates
an osmotic gradient in the eye between plasma, and ocular fluid,
reducing intraocular pressure, and hypotension.
Major side effects: Headache, confusion, disorientation, dizziness, syncope, hypernatremia,
decreased urinary output
Treatment: Glaucoma: To alleviate acute attacks; it poses less risk of nausea and
vomiting than other oral osmotic agents; short-term reduction of
intraocular pressure before and after ocular surgery
URINARY TRACT INFECTION
◆ Drugs to Treat Urinary Tract Infection
Generic Name Trade Name
Phenazopyridine PyridiumMethylene blue Urolene BlueCo-trimoxazole Bactrim, SeptraNitrofurantoin Furadantin, MacrodantinCephalexin Keflex
• Pyridium
Desired effect: Pyridium is used for the relief of symptoms of pain and burning; used with
urinary anti-infectives
Major side effects: Renal and hepatic toxicity, yellow-orange urine, hemolytic anemia,
hemolytic anemia, rash, headache
Treatment: Symptomatic relief of pain, urgency, burning, frequency, and discomfort
related to irritation of the lower urinary tract mucosa caused by
infection, trauma, surgery, or endoscopic procedures.
• Urolene Blue
Desired effects: Urinary tract anti-infective
Major side effects: Dizziness, headache, mental confusion, nausea, vomiting, blue-green
stools, discolored urine (blue-green), bladder irritation
(continued)
40 ◆ Chapter 4
◆ Drugs to Treat Urinary Tract Infection (continued)
Generic Name Trade Name
Urolene Blue (continued)
Treatment: Cyanide poisoning and drug-induced methemoglobinemia; GU
antiseptic for cystitis and urethritis
• Bactrim, Septra
Desired effect: Antibacterial
Side effects: Hemolytic anemia, low white blood cell and platelet counts,
thrombocytopenia, aplastic anemia (rare), nausea, vomiting
Treatment: Urinary tract infection
Furadantin, Macrodantin
Desired effect: Urinary tract anti-infective
Major side effects: Anorexia, drowsiness, vertigo, pruritus, asthma attack, nausea, vomiting
Treatment: Urinary tract infection caused by susceptible strains of Escherichia coli,Staphylococcus aureus, Klebsiella, Enterobacter, and Proteus spp.;
prophylaxis or long-term suppression of UTIs
• Keflex
Desired effects: Bactercidal: Inhibits synthesis of bacterial cell walls, causing cell death
Side effects: Bone marrow depression, anaphylaxis, pseudomembranous colitis, liver
toxicity, dizziness, headache, anorexia, rash, anaphylaxis, diarrhea
Treatment: Respiratory tract infections caused by Streptococcus pneumoniae or group
A beta hemolytic streptococci; dermatologic infections caused by
staphylococci or streptococci; otitis media caused by S. pneumoniaeor Haemophilus influenzae; bone infection caused by staphylococci or
Proteus mirabilis; GU infections caused by E. coli or Klebsiella
HYPOTENSIVE AGENTS
◆ Hypotensive Agents
Generic Name Trade Name
Dopamine No commonly used trade name
Epinephrine (adrenaline) No commonly used trade name
Norepinephrine LevophedAramine No commonly used trade name
Desired effects: Increase blood pressure (cause vasoconstriction and increase heart rate)
Major side effects: Nervousness, tachycardia, hypertension, arrhythmias, angina
Treatment: Hypotension, bradycardia, and COPD
Drugs that Affect Fluid and Electrolyte Balance ◆ 41
VOLUME EXPANDERS
◆ Volume Expanders
Generic Name Trade Name
Plasma PlasmanateAlbumin • Albuminar
Dextran • Gentran
Desired effects: Maintain plasma colloid osmotic pressure and aid intermediate metabolites in
the transport and exchange of tissue products; important in the
maintenance of normal blood volume
Side effects: Pulmonary edema, fever, chills, nephrotoxicity (with rapid IV infusion),
hypertension, hypotension, tachycardia, nausea, vomiting, rash, headache,
dyspnea
Treatment: Volume deficit and hypoproteinemia; hemolytic disease in newborns; binds
free bilirubin (pending exchange transfusion); hypotension; ascites; severe
burns; hypovolemic shock; other causes of severe fluid volume deficit
Desired effect: Expansion of plasma volume, increase of protein, maintenance of cardiac
output in situations associated with deficiencies in circulatory volume,
bring fluid (edema) back into the vascular system, and hold fluid within
the vascular system
Chapter
5 Cardiovascular Drugs
You have already studied many drugs used for cardiovascular disorders in Chapters 2and 4; refer also to Chapter 6.
The new drug classifications presented in this section are:
1. Angiotensin-converting enzyme inhibitors (ACEIs)
2. Calcium channel blockers
3. Agents that selectively dilate arterioles
4. Nipride, a selective venous and arteriolar dilator
5. Inotropic drugs
6. Sodium channel blockers
7. Organic nitrates
ANGIOTENSIN-CONVERTING ENZYME INHIBITORS
1. Angiotensin-converting enzyme inhibitors (ACEIs) are important drugs for treat-ing hypertension and congestive heart failure.
2. The primary effect of these drugs is vasodilation, resulting from inhibition of therenin-angiotensin-aldosterone system.
42
Cardiovascular Drugs ◆ 43
3. The rate at which renin is released from the kidney determines the amount ofangiotensin II and aldosterone formation.
4. Angiotensin II is an extremely potent vasoconstrictor, most prominently in arteri-oles. When angiotensin II is inhibited, vasodilation occurs.
5. Captopril (Capoten) was the first ACE inhibitor to be widely employed. The drugis administered orally to treat hypertension and congestive heart failure. There arenow several other widely used ACEIs (e.g., enalapril [Vasotec]).
6. The pharmacological effects of these drugs result from inhibition of ACE. Byinhibiting ACE, the drugs prevent conversion of angiotensin I into angiotensin II,a potent vasoconstrictor, and stimulation of aldosterone release.
7. The major response to reduced angiotensin II production is vasodilation, primarilyin arterioles, and to a lesser degree, in veins.
NURSING IMPLICATIONS
1. Reduced aldosterone release (secondary to reduced angiotensin II) promotes renalretention of potassium and increased excretion of sodium and water.
2. ACE inhibitors offer several advantages over other antihypertensive drugs. Theycan be used safely in patients with bronchial asthma, a condition that precludesthe use of beta-adrenergic blocking agents.
3. ACEIs do not promote hypokalemia, hyperuricemia, or hyperglycemia; these sideeffects are seen in patients using thiazide diuretics.
4. ACEIs do not induce lethargy, weakness, or sexual dysfunction—common re-sponses to the older antihypertensive agents.
5. ACEIs produce multiple benefits in patients with congestive heart failure (CHF).
6. By lowering arteriolar tone, ACEIs improve regional blood flow, and by reducingcardiac afterload, increase cardiac output.
7. By dilating blood vessels in the kidney, the drug increases renal blood flow, therebypromoting excretion of sodium and water.
◆ Angiotensin-Converting Enzyme Inhibitors (ACEIs)
Generic Name Trade Name
Captopril CapotenBenazepril HCl LotensinEnalapril VasotecTrandolapril MavikEnalaprilat Vasotec I.V.Lisinopril Prinivil, Zestril
(continued)
44 ◆ Chapter 5
◆ Angiotensin-Converting EnzymeInhibitors (ACEIs) (continued)
Generic Name Trade Name
Quinapril HCl AccuprilRamipril AltraceFosinopril sodium MonoprilMoexipril UnivascPerindopril • Aceon
Desired effect: Suppression of the renin-angiotensin-aldosterone system
Major side effects: First-dose hypotension is most likely in patients with severe hypertension who are
taking diuretics and who are volume depleted; persistent, dry, irritating,
nonproductive cough; hyperkalemic inhibition of aldosterone release
(secondary to inhibition of angiotensin II production) can cause potassium
retention by the kidney; as a rule, significant potassium accumulation is limited
to patients taking potassium supplements or potassium-sparing diuretics or
who are in renal failure.
Treatment: Hypertension and congestive heart failure
Nursing implications: ACEIs are contraindicated for patients with renal artery stenosis, because their
potassium is already above the normal serum level of 3.5–5.0 mEq/L;
contraindicated during the second and third trimesters of pregnancy, because
potassium is already above normal; ACEIs can increase serum lithium levels,
causing toxicity.
CALCIUM CHANNEL BLOCKERS
1. Calcium channel blockers are drugs that prevent calcium ions from entering cells.These drugs have their greatest effect on the heart and blood vessels.
2. Calcium channel blockers reduce blood pressure by causing vasodilation of pe-ripheral arterioles, arteries, and arterioles of the heart.
3. Over the last decade, the calcium channel blockers have assumed a prominent rolein the treatment of hypertension, angina pectoris, and myocardial infarction (MI),as well as cardiac dysrhythmias.
NURSING IMPLICATIONS
1. Calcium channel blockers, beta-adrenergic blockers, and digoxin have two of thesame effects—decreased heart rate and decreased A-V conduction. Remember,digoxin not only decreases cardiac rate but also increases the force of cardiac
Cardiovascular Drugs ◆ 45
contractions, thereby increasing cardiac output, and it is also used to treat atrialdysrhythmias.
2. Therefore, the nurse must take the patient’s apical pulse before administering thesemedications. If the pulse is below 60 beats per minute in adults, the drug is withheldand the physician notified.
3. Beta-adrenergic blockers and calcium channel blockers cause peripheral vasodi-lation; therefore, blood pressure must also be taken before their administration.
4. The nurse must take the patient’s blood pressure before administering calciumchannel blockers or beta-adrenergic blockers because they lower the blood pres-sure. If the patient’s blood pressure is significantly lower than his or her baseline,hold the medication and notify the physician. For example, if the patient’s base-line blood pressure is 180/100 mm Hg and it is now 110/70 mm Hg, withholdthe medication and notify the physician. While the purpose of these drugs is todecrease blood pressure, it should not go below the patient’s normal blood baselinepressure.
5. Calcium channel blockers decrease myocardial contractility, thereby decreasingthe workload of the heart; that is why this drug class is used to treat myocardialinfarction (MI) and for treatment of arrhythmias.
◆ Calcium Channel Blockers
Generic Name Trade Name
Amlodipine NorvascIsradipine • DynaCirc, DynaCirc CR
Bepridil VascorDiltiazem Cardizem, Cardizem CDFelodipine PlendilNicardipine CardeneNifedipine Adalat, ProcardiaNimodipine • Nimotop
Nisoldipine • Sular
Verapamil Calan, IsoptinDesired effect: Decrease angina pain, management of hypertension and arrhythmias
Side effects: Headache, arrhythmias, hypotension, fatigue, dizziness
Treatment: Hypertension, angina, and cardiac arrhythmias
Notes: Calcium channel blockers relax arterial smooth muscle, depress the rate of the sinus node pacemaker, slow A-V
conduction, and decrease heart rate. All calcium channel blockers decrease coronary vascular resistance, increase coronary
blood flow, and reduce myocardial oxygen demand. Nifedipine should be used with great caution if at all because of the
risk of death according to the National Heart, Lung and Blood Institute. Calcium blockers cannot be discontinued abruptly; a
physician must be consulted.
46 ◆ Chapter 5
VASODILATORS
Vasodilation can be produced with a wide variety of drugs. Some of these drugs actprimarily on arterioles, some act primarily on veins, and some dilate both types ofvessels.
1. Vasodilators are widely used, ranging from the treatment of hypertension to anginapectoris to heart failure.
2. Five vasodilator agents are introduced here: hydralazine (Apresoline), minoxidil(Loniten, Rogaine), diazoxide (Hyperstat IV), nitroprusside (Nipride, Nitropress),and nitroglycerin.
3. All other commonly used cardiovascular vasodilators are discussed inChapter 2.
4. The selectivity of a vasodilator determines its hemodynamic effects. For example,dilators of resistance vessels (arterioles) cause a decrease in cardiac afterload (theforce against which the heart must work to pump blood).
5. By decreasing afterload, arteriolar dilators reduce cardiac work, while at the sametime increasing cardiac output and tissue perfusion.
◆ Types of Vasodilators
Category Examples
Angiotensin-converting
enzyme inhibitors
Vasotec, Capoten, Zestril (presented in this chapter)
Organic nitrates Nitroglycerin, Nitro-Bid, Nitrostat, Nitropress (presented
in this chapter)
Calcium channel blockers Cardizem, Procardia, Calan, Isoptin (presented in
this chapter)
Alpha-adrenergic blockers Catapres, Minipress, Serpasil, Hytrin, Rogitine,Dibenzyline (presented in Chapter 2)
Beta-adrenergic blockers Tenormin, Betoptic, Lopressor, Corgard, Inderal,
Timoptic (presented in Chapter 2)
Adrenergic neuron
blockers
Reserpine, Ismelin (presented in Chapter 2)
Central-acting agents Catapres, Aldomet (presented in Chapter 2)
Agents that selectively
dilate arterioles
Apresoline, Loniten, Hyperstat (presented in this
chapter)
Selective venous and
arteriolar dilator
Nipride (presented in this chapter)
Note: Drugs are listed by the most commonly used name.
Cardiovascular Drugs ◆ 47
◆ Agents that Selectively Dilate Arterioles (Reduce Afterload)
Generic Name Trade Name
Hydralazine ApresolineMinoxidil LonitenDiazoxide Hyperstat IV (Increase blood glucose)
�Apresoline
Desired effect: Acts directly on vascular smooth muscle to cause vasodilation, primarily
arteriolar; maintains or increases renal and cerebral blood flow
Major side effects: Headache, palpitations, tachycardia, angina pectoris, anorexia, nausea,
vomiting, nasal congestion
Treatment: Oral: Essential hypertension alone or in combination with other agents;
Parenteral: Severe essential hypertension when drug cannot be given
orally or when the need to lower blood pressure is urgent
Nursing implications: Educate the patient to take the drug exactly as prescribed; take medication
with food; do not discontinue or reduce dosage without consulting the
health care provider; advise the patient about the side effects of the
medication and to report persistent chest pain, constipation, unexplained
fever or malaise, muscle or joint pain, rash, numbness, and tingling.�Loniten
Desired effects: Acts directly on vascular smooth muscle to cause vasodilation, reducing
elevated systolic and diastolic BP; does not interfere with CV reflexes,
but does cause tachycardia and renin release, leading to sodium and
water retention.
Major side effects: Fatigue, headache, tachycardia (unless given with a beta-adrenergic blocker
or other sympatholytic drug); temporary edema, irritant dermatitis, allergic
contact dermatitis, eczema, pruritus, dry skin
Treatment: Severe hypertension that is symptomatic or associated with target organ
damage and is not manageable with maximum therapeutic doses of a
diuretic plus two other antihypertensive drugs; use in milder hypertension
is not recommended; topical use for alopecia
Nursing implications: Advise the patient that if they apply the topical preparation to an affected
area, to use the fingers and wash hands thoroughly afterward. Oral: Take
this drug exactly as prescribed, and take all other medications that have
been prescribed. Do not discontinue any drug or reduce dosage without
consulting the health care provider.
Educate the patient about signs and symptoms associated with the drug and
to report them to the health care provider (e.g., increase in heart rate).�Hyperstat
Desired effects: Increases blood glucose by decreasing insulin release; decreases BP by
relaxing arteriolar smooth muscle
Major side effects: MI, angina, CHF (secondary to fluid and sodium retention), cerebral
ischemia, thrombocytopenia, hyperglycemia, glycosuria, ketoacidosis
and nonketotic hyperosmolar coma, headache, seizures, blurred vision
(continued)
48 ◆ Chapter 5
◆ Agents that Selectively Dilate Arterioles (Reduce Afterload)(continued)
Generic Name Trade Name
Hyperstat (continued)
Treatment: Oral: Management of hypoglycemia due to hyperinsulinism in infants and
children, and to inoperable pancreatic islet-cell malignancies; Parenteral:
Short-term use in malignant and nonmalignant hypertension; used
primarily in hospitals
Nursing implications: Monitor intake and output and weigh patient daily at the same time to
check for fluid retention; have insulin and tolbutamide (an oral
antidiabetic agent) readily available in case a hyperglycemic reaction
occurs; have dopamine and norepinephrine readily available in case of
severe hypotension.
◆ Nipride: A Selective Venous and Arteriolar Dilator(Reduces Afterload and Preload)
Generic Name Trade Name
Nitroprusside NiprideDesired effect: Rapid lowering of blood pressure
Side effects: Retention of sodium and water; Lasix used with Nipride can help offset this effect
because two of the side effects of Lasix are dehydration and hyponatremia; if
administered too rapidly, Nipride can cause a precipitous fall in blood
pressure, resulting in headache, palpitations, nausea, vomiting, and sweating.
Treatment: Drug of choice for treating hypertensive emergencies
Nursing implications: Blood pressure and heart rate should be monitored frequently; if severe
hypotension occurs, drug effects are quickly reversed by decreasing the rate or
temporarily discontinuing the infusion; it is also necessary to monitor for
rebound hypertension following discontinuation of Nipride; pulmonary
capillary wedge pressure (PCWP) is usually monitored in clients with acute
CHF or severe hypertension while receiving IV Nipride; plasma cyanide
(thiocyanate levels) should be monitored every 48–72 hours; Nipride
contains five cyanide groups, which are converted into thiocyanate in the
liver; signs and symptoms of cyanide poisoning include rapid respirations, later
becoming slow and gasping; choking feeling; anxiety; dizziness; confusion;
headache; pulse rapid, feeble, and irregular; if not treated, the patient will
become unconscious and die.
Treatment: Treatment for cyanide poisoning includes amyl nitrate inhalation and infusion of
sodium nitrate.
Notes: Reflex tachycardia is minimal. Dilators of veins and arterioles cause a reduction in cardiac preload (the force with which
blood is returned to the heart). By decreasing preload, venous dilators cause a decrease in cardiac filling and cardiac workload,
along with a decrease in cardiac output and tissue perfusion. (Preload is another name for diastole [e.g., venous blood is
returning to the heart]. Afterload is another name for systole [e.g., arterial blood is pumped out of the heart].)
Nipride must be covered with a paper bag while being administered.
Cardiovascular Drugs ◆ 49
INOTROPIC AGENTS
The cardiac glycosides (e.g., digoxin) are the oldest and most frequently prescribed in-otropic drugs (drugs influencing the force of cardiac contraction). Three types of inotropicdrugs are available: (1) cardiac glycosides, (2) adrenergic agents [e.g., epinephrine], and(3) phosphodiesterase (PDE) inhibitors (e.g., amrinone).
NURSING IMPLICATIONS
The adrenergic agents (catecholamines) and the PDE inhibitors currently available canonly be administered intravenously. At this time, the cardiac glycosides are the onlyinotropic agents that can be used orally. Therefore, these are the only inotropics suitedfor long-term chronic treatment of CHF.
◆ Cardiac (Digitalis) Glycosides
Generic Name Trade Name
Digoxin LanoxinTreatment of: Congestive heart failure (CHF) and atrial dysrhythmias
Desired effect: Increase the force of ventricular contraction, and thereby increase cardiac output
Side effects: Production of dysrhythmias is the most serious adverse effect of digoxin.
The drug causes dysrhythmias by altering the electrical properties of the heart.
Digoxin can mimic practically all types of dysrhythmias.
A-V block due to digoxin is one of the most common causes of bradycardia.
Ventricular flutter and ventricular fibrillation are the most dangerous side effects.Other side effects include fatigue, weakness, blurred vision, yellow vision, and
anorexia.
Nursing implications: The most common cause of dysrhythmias in clients receiving digoxin is hypokalemia
secondary to the use of diuretics that are not potassium-sparing; less common
causes of hypokalemia include vomiting and diarrhea.
Hypokalemia promotes dysrhythmias by increasing digoxin’s ability to increase
automaticity of Purkinje fibers.
Because low potassium can precipitate dysrhythmias, it is imperative that serum
potassium levels be kept within the normal range.
If diuretic therapy causes potassium levels to fall, a potassium-sparing diuretic (e.g.,
spironolactone) can be added to the regimen to correct the problem; potassium
supplements may also be used.
Patients must be taught to recognize symptoms of hypokalemia (e.g., muscle weakness)
and be instructed to notify the physician if these develop.
Digoxin has a narrow therapeutic range; drug levels only slightly higher than the
therapeutic level greatly increase the risk of toxicity.
If plasma digoxin levels are monitored and kept within the therapeutic range, the
chances of dysrhythmia will be reduced.
For digoxin, the usual therapeutic range is 0.05–2.0 ng/mL; levels above 2.5 ng/mLare toxic; do not confuse this with the loading dose, which is 0.75–1.25 mg PO.
(continued)
50 ◆ Chapter 5
◆ Cardiac (Digitalis) Glycosides (continued)
Generic Name Trade Name
Amrinone InocorMilrinone PrimacorTreatment of: Treatment of CHF in patients who have not responded to digoxin,diuretics, and
vasodilators; Inocor or Primacor are indicated for short-term (2–3 days) treatment
of CHF.
Desired effect: Increase in myocardial contractility and promotion of vasodilation; comparative
studies indicate that improvement in cardiac function elicited by Inocor and
Primacor are superior to those elicited by dopamine or dobutamine.
Nursing implications: Like dopamine and dobutamine, Inocor and Primacor are administered by
intravenous infusion, and therefore are not suitable for outpatient use.
Notes: Remember, adrenergic agents used for inotropic effects (e.g., increase in the force of cardiac contractions) are
covered in Chapter 2.
Phosphodiesterase inhibitors are also inotropic agents; see later in this chapter.
Take apical pulse before administration of digoxin. Do not give if pulse is below 60 beats per minute and call a physician.
DRUGS FOR DYSRHYTHMIAS
SODIUM CHANNEL BLOCKERS
Quinidine is the oldest and most thoroughly studied sodium channel blocker. By block-ing sodium channels, quinidine slows impulse conduction in the atria, ventricles, andHis-Purkinje system. In addition, the drug delays repolarization of these sites. Both ac-tions contribute to suppression of dysrhythmias. Quinidine is strongly anticholinergic(atropinelike) and blocks vagal input to the heart.
◆ Sodium Channel Blockers
Generic Name Trade Name
Quinidine No commonly used trade name
Treatment of: The principal indication for quinidine is long-term suppression of
dysrhythmias, including supraventricular tachycardia, atrial flutter, atrial
fibrillation, and sustained ventricular tachycardia.
Side effects: Diarrhea, hypotension, tinnitus (ringing in the ears), headache, vertigo,
sinus arrest, and A-V block
Nursing implications: The ECG will change with quinidine overdose, which will cause
cardiotoxicity; important danger signals are widening of the QRS
complex and excessive prolongation of the QT interval; the
physician should be notified immediately if these changes occur.
Cardiovascular Drugs ◆ 51
◆ Sodium Channel Blockers (continued)
Generic Name Trade Name
Procainamide PronestylTreatment of: Pronestyl is similar to quinidine in action and applications; like quinidine
it is used to treat a broad spectrum of dysrhythmias; unfortunately,
serious side effects limit the drug’s use.
Side effects: Prolonged treatment with Pronestyl is associated with severe
immunologic reactions; other side effects are hypotension, blood
dyscrasias, and cardiotoxicity, indicated on ECG by QRS widening
and excessive prolongation of the QT interval.
Lidocaine XylocaineTreatment of: Lidocaine, an intravenous agent, is only used to treat ventricular
dysrhythmias; in addition to its antidysrhythmic application, lidocaine
is employed as a local anesthetic.
Side effects: Lidocaine is generally well tolerated; however, adverse central nervous
system effects can occur.
Nursing implications: High therapeutic doses can cause drowsiness, confusion, paresthesias,
convulsions, hypotension, bradycardia, and heart block.
Mexiletine MexitilTocainide TonocardTreatment: Mexitil and Tonocard, oral congeners of lidocaine, are used to treat
ventricular dysrhythmias and ventricular tachycardia.
Side effects: Same side effects as lidocaine
Phenytoin DilantinTreatment of: Dilantin is an antiseizure drug that is also used to treat digoxin-induced
dysrhythmias; Dilantin is presented in Chapter 3 (antiseizure agents);
discussion here is limited to its antidysrhythmic applications.
Side effects: Sedation, ataxia, and nystagmus
Nursing implications: With too rapid IV administration, Dilantin can cause hypotension,
dysrhythmias, and cardiac arrest; gingivitis and hyperplasia of the
gums is a frequent complication of long-term use; may also cause
pink, red, or reddish-brown discoloration of urine.
Note: Dilantin is a second-line drug after lidocaine for treatment of digoxin-induced dysrhythmias.
DRUG THERAPY FOR HYPERTENSION
You have already studied the other drugs used for hypertension in prior chapters. Thisadditional information will help you understand the therapeutic regimen used in thetreatment of hypertension. Treatment of hypertension has two objectives: to reducesystolic and diastolic blood pressure and to prevent long-term complications. Lifestylechanges can adequately decrease blood pressure in many people, thus eliminating theneed for drug therapy.
52 ◆ Chapter 5
DIURETICS
Diuretics are a mainstay of antihypertensive therapy. These drugs reduce the bloodpressure when used alone and they can enhance the effects of other hypotensive agents.Diuretics are presented in Chapter 4.
Thiazide Diuretics
1. Thiazides (e.g., HydroDIURIL) are the most commonly used antihypertensivediuretics. Thiazides reduce blood pressure by two mechanisms: reduction of bloodvolume and reduction of arterial resistance.
2. High-ceiling loop diuretics: High-ceiling loop diuretics (e.g., Lasix) produce muchgreater diuresis than thiazides. Like the thiazides, the loop diuretics lower bloodpressure by reducing blood volume. Loop diuretics do not promote vasodilation;remember that the thiazides will reduce arterial pressure.
3. Potassium-sparing diuretics: The degree of diuresis induced by potassium-sparingdiuretics (e.g., Aldactone) is small. However, these drugs can play an importantrole in an antihypertensive regimen. Their role is to balance potassium loss causeby thiazide or loop diuretics.
BETA-ADRENERGIC BLOCKERS
1. The beta blockers (e.g., Inderal, Lopressor) are among the most commonly usedantihypertensive drugs. Beta-adrenergic blockers are presented in Chapter 2. Thebeta blockers have at least three useful actions in the treatment of hypertension:
a. Blockade of cardiac beta-1 receptors in the heart decreases heart rate and cardiaccontractility, thereby decreasing cardiac output.
b. When there is peripheral vasodilation, the heart senses hypotension and willcompensate with tachycardia.
c. Blockage of beta-1 receptors in the kidney reduces the release of renin, therebyreducing vasoconstriction; therefore, vasodilation occurs. Reduced aldosteronereduces sodium and water retention. Both of these actions reduce bloodpressure.
2. Beta-adrenergic blockers can produce a variety of adverse effects. Three of themore dangerous effects are:
a. Bradycardia
b. Decreased atrioventricular (A-V) conduction
c. Reduction of cardiac contractility
3. Beta-1 adrenergic blockers should not be used by patients with the followingmedical problems:
a. Sick sinus syndrome
b. Congestive heart failure
c. Second- or third-degree A-V block
Note: Beta-1 receptors are present in the heart.
Cardiovascular Drugs ◆ 53
Blockage of beta-2 adrenergic receptors in the lungs can produce bronchoconstric-tion (adrenaline is blocked); therefore, patients with chronic obstructive pulmonary dis-ease (COPD) should not be given beta-2 blockers. If a COPD patient must use a betablocker, a beta-1–selective agent (e.g., Lopressor) should be employed. (Beta-1 receptorsare not present in the lungs. They are found in the heart and the kidneys.)
OTHER AGENTS
Central-Acting Alpha-Adrenergic Inhibitors
Central-acting alpha-adrenergic inhibiting agents (e.g., Catapres, Aldomet) act withinthe brainstem to suppress sympathetic outflow to the heart and blood vessels.
1. By suppressing sympathetic vasoconstriction of the blood vessels, these drugspromote vasodilation, bradycardia, and reduced cardiac output.
2. Blood pressure is reduced in both the supine and standing positions, unlike theperipheral alpha-adrenergic blockers, which tend to decrease blood pressure onlywhen the patient is standing.
3. Central-acting alpha-adrenergic inhibiting agents are presented in Chapter 2.
Calcium Channel Blockers
These reduce blood pressure by causing vasodilation of peripheral arterioles, arteries,and arterioles of the heart. Calcium channel blockers are presented in this chapter.
Angiotensin-Converting Enzyme Inhibitors
These are the most frequently used drugs for controlling hypertension.
Selective Vasodilators
The selective vasodilators include Apresoline, Loniten, and Nipride. Diazoxide (Hyper-stat IV) reduces blood pressure by dilation of arterioles. Venous and arteriolar dilators(e.g., Nipride) reduce blood pressure by dilation of venous and arteriolar vessels. Selec-tive vasodilators are presented in this chapter.
Adrenergic Neuron Blockers
The adrenergic neuron blockers (e.g., Reserpine, Ismelin) reduce blood pressure by re-ducing the release of norepinephrine from sympathetic neurons. They act presynaptically.Adrenergic neuron blockers are presented in Chapter 2.
Note: By activating beta-1 receptors, epinephrine increases cardiac output, therebyhelping to elevate blood pressure. Blood pressure is also increased because ofepinephrine’s ability to activate alpha-1 receptors in the peripheral vascular system,causing vasoconstriction. By activating beta-2 receptors in the lungs epinephrine cancounteract bronchoconstriction.
Norepinephrine can activate alpha-1 receptors in the peripheral vascular system,causing vascular constriction, and beta-1 receptors in the heart, increasing cardiac output.Dopamine receptor activation is discussed in Chapter 2.
54 ◆ Chapter 5
DRUG THERAPY FOR CARDIAC DYSRHYTHMIAS
You have already studied the drugs used to treat cardiac dysrhythmias in this handbook.The drug classification listed here is to help you know the therapeutic regimens used totreat cardiac dysrhythmias.
1. Sodium channel blockers (e.g., quinidine, lidocaine) are presented in this chapter.
2. Calcium channel blockers (e.g., Calan, Isoptin) are presented in this chapter.
3. Beta-adrenergic blockers (e.g., Lopressor, Inderal) are presented in Chapter 2.
4. Muscarinic anticholinergic drugs (e.g., atropine) are presented in Chapter 2.
5. Miscellaneous drugs (e.g., adenosine) are presented in this chapter.
◆ Miscellaneous Drugs for Dysrhythmias
Generic Name Trade Name
Adenosine • Adenocard
Treatment of: Paroxysmal supraventricular tachycardia (PSVT)1
Desired effect: Normal sinus rhythm in patients diagnosed with PSVT
Side effects: Atrial tachydysrhythmia, hypotension, dyspnea, dizziness
Nursing implications: Adenosine slows conduction through the A-V node.
Amiodarone HCl Cordarone, PaceroneTreatment of: Use only for treatment of the following documented life-threatening recurrent
ventricular arrhythmias that do not respond to other interventions or when
alternative agents are not tolerated: recurrent ventricular fibrillation, recurrent
hemodynamically unstable ventricular tachycardia; serious and even fatal
toxicity has been reported with this drug; use alternative agents first; monitor
patients receiving this drug very closely.
Desired effect: Type III antiarrhythmic that acts directly on the cardiac cell membrane; prolongs
repolarization and the refractory period; increases the ventricular fibrillation
threshold; acts on peripheral smooth muscle cells to decrease peripheral
resistance
1An apical pulse must be taken before administering adenosine. This drug is contraindicated in second- and third-degree heart
block.
DRUG THERAPY FOR MYOCARDIAL INFARCTION
Thrombolytic agents and anticoagulants used to treat myocardial infarction (MI) arepresented in Chapter 6. The drug classification listed here is to help you know thetherapeutic regimen used to treat an MI.
1. Morphine is given to reduce pain and thereby reduce the release of catecholamines,which decreases cardiac workload, and is presented in Chapter 3.
Cardiovascular Drugs ◆ 55
2. Thrombolytic agents (e.g., streptokinase, urokinase) are presented in Chapter 6.
3. Anticoagulants (e.g., heparin, Coumadin, aspirin) are presented in Chapter 6.
DRUG THERAPY FOR HEART FAILURE
You have already studied the drugs used to treat heart failure in this handbook. The drugclassification listed here is to help you know the therapeutic regimens used to treat heartfailure.
1. High-ceiling (loop) diuretics (e.g., Lasix, Edecrin) are presented in Chapter 4.
2. Potassium-sparing diuretics (e.g., Aldactone, Dyrenium) are presented inChapter 4.
3. Cardiac glycosides (e.g., digoxin) are presented in detail in Chapter 2.
4. Beta-adrenergic agents (e.g., dopamine, dobutamine) are presented in Chapter 2.
DRUG THERAPY FOR ANGINA PECTORIS
You have already studied the drugs used to treat angina pectoris in this handbook. Thedrug classification listed here is to help you know the therapeutic regimens used to treatangina pectoris.
1. Organic nitrates are the oldest and most frequently used antianginal drugs. Theseagents relieve angina by causing vasodilation of veins and arteries, decreasingpreload and afterload. Nitroglycerin is the most frequently used organic nitrate.
2. Calcium channel blockers decrease the pain primarily by dilating arterioles, thusreducing the amount of blood returning to the ventricles; this reduces the workloadof the heart and thus reduces cardiac oxygen demand, thereby relieving pain.
a. Classic angina is triggered by an increase in activity, emotional excitement,large meals, and exposure to cold. The underlying cause is coronary arterydisease (deposits of plaque in the coronary arteries).
b. In variant angina, also called vasospastic angina, the patient experiences painat rest due to coronary artery vasospasm.
c. Unstable angina due to coronary artery vasospasm occurs when the patient isat rest, with symptoms gradually occurring more frequently and lasting longer.Unstable angina does not respond well to medications such as calcium blockers,nitroglycerin, or beta blockers.
d. Nitroglycerin redistributes blood flow to ischemic myocardial areas, and im-proves perfusion without an increase in coronary blood flow. The principaladverse effects of nitroglycerin are headache, hypotension, and tachycardia.
Chapter
6 Drugs that Affectthe Blood
The drugs discussed in this section are used to prevent formation of thrombi (intravascularblood clots) and to remove thrombi that have already formed. These drugs act in severalways: some suppress coagulation, some inhibit platelet aggregation, and some promoteclot dissolution. All of these drugs interfere with normal hemostasis; therefore, theycarry a significant risk of hemorrhage.
◆ Oral Anticoagulant
Generic Name Trade Name
Warfarin CoumadinDesired effects: Interferes with the hepatic synthesis of vitamin K–dependent clotting factors
(factors II, VII, IX, and X, and prothrombin), resulting in their eventual
depletion and prolongation of clotting time.
Treatment: Coumadin is used to prevent thrombosis; in contrast to heparin, Coumadin has a
delayed onset of action, which makes it inappropriate for emergency use; it is
employed most frequently for long-term prophylaxis of thrombosis; initial
response to Coumadin may not be evident until 8–12 hours after
administration; its peak effects do not develop for several days; therefore, the
physician will start the patient on Coumadin 2–3 days prior to discontinuing
the heparin.
56
Drugs that Affect the Blood ◆ 57
ASPIRIN
Antiplatelet therapy with aspirin has three applications: (1) prevention of acute myocar-dial infarction (MI) in clients with unstable angina, (2) prevention of reinfarction inclients who have experienced an acute MI, and (3) prevention of stroke in clients witha history of transient ischemic attacks (TIAs). Other classifications for aspirin includeanalgesic, antirheumatic, salicylate, and nonsteroidal anti-inflammatory drug (NSAID).
◆ Vitamin K Antagonist
Generic Name Trade Name
Warfarin CoumadinDesired effects: Coumadin interferes with the hepatic synthesis of vitamin K, resulting in
prolongation of clotting time; vitamin K is also an antiplatelet drug, and
therefore inhibits clotting.
Treatment: Used to prevent vascular thrombosis
Side effects: Bleeding is the major complication.
Nursing implications: After Coumadin is discontinued; coagulation remains inhibited for 2–5 days;
this residual effect is due to its long half-life.
Monitoring: The anticoagulant effects of Coumadin are evaluated by monitoring
prothrombin time (PT), a coagulation test; the average normal PT is
11–12.5 seconds; treatment with Coumadin prolongs the PT.
Antidote: The effects of Coumadin overdose can be overcome with vitamin K,
(AquaMEPHYTON); vitamin K is an antagonist of Coumadin and will
reverse Coumadin-induced inhibition of clotting factor synthesis.
◆ Antiplatelet Drugs
Generic Name Trade Name (Route)
Aspirin Bayer, Ecotrin (PO)
Dipyridamole Persantine, Dipridacot (PO, IV) [Canada]
Abciximab ReoPro (IV)
Cilostazol Pletal (PO)
Clopidogrel Plavix (PO)
Sulfinpyrazone Anturane (PO) [Canada]
Ticlopidine Ticlid (PO)
• Aspirin
Desired effects: Higher doses of aspirin inhibit the synthesis of prostacyclin, a potent vasodilator
and inhibitor of platelet aggregation; analgesic and anti-inflammatory effects are
attributed to aspirin’s ability to inhibit the synthesis of prostaglandin.
(continued)
58 ◆ Chapter 6
◆ Antiplatelet Drugs (continued)
Generic Name Trade Name (Route)
�Aspirin (continued)
Side effects: Thrombocytopenia, agranulocytosis, leukopenia, neutropenia, hemolytic anemia,
increased prothrombin time, nausea, vomiting, GI bleeding, diarrhea,
heartburn, anorexia, hepatitis, Reye’s syndrome seizures
Treatment: Used for moderate pain or fever including rheumatoid arthritis, osteoarthritis,
thromboembolic disorders, transient ischemic attacks, rheumatic fever,
post–myocardial infarction, prophylaxis of MI, ischemic stroke, angina
Nursing implications: Liver function studies (AST, ALT); bilirubin if patient is on long-term therapy;
renal function studies; BUN; urine creatinine if patient is on long-term therapy�Dipyridamole
Desired effects: Decreases coronary vascular resistance and increases coronary blood flow without
increasing myocardial oxygen consumption; inhibits platelet aggregation;
interferes with platelet membrane function by inhibiting fibrinogen binding and
platelet-platelet interactions; prolongs bleeding time
Side effects: MI, ventricular fibrillation (IV); respiratory: bronchospasm (IV); GU: possible
decreased fertility and loss of eggs in women
Nursing implications: Provide continual monitoring of ECG, BP, and orientation during administration of
IV dipyridamole; administer oral drug at least 1 hour before meals with a full
glass of fluid
Treatment: PO: persantine is used to prevent thromboembolism in patients with prosthetic
heart valves; IV: diagnostic aid in evaluation of coronary artery disease (CAD)
in patients who cannot exercise, and as an alternative to exercise in thallium
myocardial perfusion imaging studies; unlabeled uses: prevention of MI or
reduction of mortality post-MI; with aspirin to prevent coronary bypass graft
occlusion�Abciximab
Desired effects: Antithrombotic monoclonal antibody; antiplatelet agent for percutaneous coronary
interventions (PCI) and acute arterial occlusive disorders
Side effects: Thrombocytopenia, bleeding, bradycardia, hypotension, arrhythmias, pneumonia,
pleural effusion
Treatment of: ReoPro is used in combination with percutaneous transluminal coronary
angioplasty or atherectomy for the prevention of acute cardiac ischemic
complications in patients at high risk for abrupt closure of the treated coronary
vessel; it is intended to be used with heparin and aspirin therapy; early
treatment of unstable angina and non-ST–segment elevation MI
Nursing implications: Monitor CBC and liver and renal function tests; history: allergy to abciximab,
neutropenia, thrombocytopenia, hemostatic disorders, bleeding ulcer,
intracranial bleeding, severe liver disease, lactation, renal disorders, pregnancy,
recent trauma�Cilostazol
Desired effects: Inhibits platelet aggregation induced by a variety of stimuli, including ADP,
thrombin, collagen, shear stress, epinephrine, and arachidonic acid by inhibiting
cAMP phosphodiesterase III (PDE III); produces vascular dilation in vascular
beds with specificity for femoral beds; seems to have no effect on renal arteries
Drugs that Affect the Blood ◆ 59
◆ Antiplatelet Drugs (continued)
Generic Name Trade Name (Route)
�Cilostazol (continued)
Side effects: Dizziness, headache, tachycardia, peripheral edema, infection and back pain
Treatment: Reduction of symptoms of intermittent claudication, allowing increased walking
distance
Nursing implications: Monitor blood clotting studies prior to and periodically during therapy; administer
drug on an empty stomach ≥30 minutes before or 2 hours after breakfast and
dinner; advise patients to use barrier contraceptives while receiving this drug, as
it may harm the fetus.�Clopidogrel
Desired effects: Inhibits platelet aggregation by blocking receptors on platelets, preventing
clumping of platelets
Side effects: Hypertension, edema, nausea, GI distress, constipation, diarrhea, GI bleeding,
increased bleeding risk
Treatment: Treatment of patients at risk for ischemic events, including history of MI, ischemic
stroke, and peripheral artery disease; treatment of patients with acute coronary
syndrome
Nursing implications: Use cautiously with bleeding disorders, recent surgery, closed head injury, or
pregnancy; potential increased risk of GI bleeding with NSAIDs, so monitor
patient carefully; potential increased bleeding with warfarin, so monitor
carefully; history: allergy to clopidogrel, pregnancy, lactation, bleeding
disorders, recent surgery, closed head injury�Sulfinpyrazone
Desired effects: Inhibits the renal tubular reabsorption of uric acid, increasing the urinary excretion
of uric acid, decreasing serum uric acid levels, retarding urate deposition, and
promoting the resorption of urate deposits; inhibits prostaglandin synthesis,
which prevents platelet aggregation, but lacks analgesic and anti-inflammatory
activity
Side effects: Exacerbation of gout and uric acid stones, renal failure, hematologic disorders,
blood dyscrasias, nausea, vomiting, diarrhea
Treatment: Inhibits platelet aggregation
Nursing implications: Report flank pain, dark urine or blood in the urine, acute gout attack, unusual
fatigue or lethargy, and unusual bleeding or bruising; take the drug with meals or
antacids to prevent GI upset; to prevent side effects (exacerbation of a gouty
attack or renal stones), drink plenty of fluids, 2.5–3 L/day; also take with meals
and use antacids; avoid the use of aspirin and aspirin-containing products;
serious toxic effects could occur.
Drug classification: These include antiplatelet agent, antigout agent, and uricosuric agent.
Nursing implications: Administer drug with meals to prevent GI upset; encourage patients to
drink 2–3 liters of fluids per day to decrease the risk of renal stone
development; check urine alkalinity (urates crystallize in acid urine);
use sodium bicarbonate or potassium citrate to alkalinize
urine
(continued)
60 ◆ Chapter 6
◆ Antiplatelet Drugs (continued)
Generic Name Trade Name (Route)
�Ticlopidine
Desired effects: Interferes with platelet membrane function by inhibiting fibrinogen binding and
platelet interactions; inhibits platelet aggregation and prolongs bleeding time;
the effect is irreversible for life of the platelets.
Side effects: Hematologic: neutropenia, thrombotic thrombocytopenic purpura, bleeding;
local: pain, phlebitis, thrombosis at injection site
Treatment: Reduces risk of thrombotic stroke in patients who have experienced stroke
Nursing implications: Decreased effectiveness of digoxin; increased serum levels and effects of
theophylline and aspirin; decreased absorption with antacids; take the drug with
meals or just after eating; patients require regular blood tests to monitor
response to this drug.
◆ Parenteral Anticoagulants
Generic Name Trade Name (Route)
Heparin No commonly used trade name (IV, SC)
Dalteparin sodium Fragmin (SC)
Enoxaparin sodium Lovenox (SC)
Tinzaparin sodium Innohep (SC)
Desired effects: • Heparin: Inactivates factor Xa, thereby inhibiting thrombus and clot formation
by blocking the conversion of prothrombin and fibrinogen to fibrin, the final
step in the clotting process; heparin also inhibits the activation of factor XIII.
• Fragmin, Lovenox, Innohep: Produces anticoagulation by inhibition of factors
Xa and IIa, preventing the formation of clots
Treatment: These anticoagulants are used to prevent vascular thrombosis, which may lead to
pulmonary thrombosis; prophylaxis for hip and abdominal surgery
Nursing implications: Monitor WBC count before use and frequently while initiating therapy; if
neutropenia is present or occurs, discontinue drug immediately; monitor for
any signs of excessive bleeding (e.g., bruises, dark stools); for heparin,
monitor activated partial thromboplastin time (aPTT)
Note: Heparin is prescribed in units, not in milligrams.
Warning: Keep protamine sulfate (1% solution) readily available in case of overdose.
THROMBOLYTIC DRUGS
As their name implies, the thrombolytic drugs act to remove thrombi that have al-ready formed. This is in contrast with the anticoagulants, which act to prevent thrombusformation.
Drugs that Affect the Blood ◆ 61
◆ Thrombolytic Drugs
Generic Name Trade Name
Alteplase Activase (tissue plasminogen activator [t-PA])
Streptokinase No commonly used trade name
Reteplase RetavaseUrokinase No commonly used trade name
Desired effect: Destroy pre-existing blood clots
Side effects: Bleeding is the major complication.
Treatment: Thrombolytic drugs have three major indications: (1) acute coronary thrombosis
(acute myocardial infarction), (2) massive pulmonary emboli, and (3) deep
vein thrombosis; in all three situations, timely intervention is essential; for
example, for treatment of coronary thrombosis (MI), best results are
obtained when thrombolytic therapy is started within 4–6 hours of the
diagnosis
Nursing implications: Regularly monitor coagulation studies; apply pressure or pressure dressings to
control bleeding (at invaded or disturbed areas); avoid any arterial invasive
procedures; arrange for typing and cross-matching of blood if serious blood
loss occurs and whole blood transfusions are required; thrombolytic drugs
can only be given by the IV route.
Several measures can reduce the risk of bleeding while a client is using
thrombolytic agents; these include: (1) avoiding subcutaneous and
intramuscular injections, (2) minimizing physical manipulation of the client,
(3) minimizing invasive procedures, (4) avoiding (whenever possible)
concurrent use of anticoagulants (e.g., heparin, Coumadin) and avoiding
concurrent use of antiplatelet drugs (e.g., aspirin).
Because of the risk of bleeding, thrombolytic drugs are absolutely
contraindicated for patients with active internal bleeding disorders; other
contraindications include recent thoracic or abdominal surgery, recent
serious trauma, and recent history of GI bleeding, organ biopsy, and lumbar
puncture.
◆ Calcium Regulator Drugs
Generic Name Trade Name
Alendronate FosamaxEtidronate DidronelCalcitonin Calcitonin (human), calcitonin (salmon)
• Fosamax
Desired effects: Slows normal and abnormal bone resorption without inhibiting bone formation
and mineralization
(continued)
◆ Calcium Regulator Drugs (continued)
Generic Name Trade Name
• Fosamax (continued)
Side effects: Headache, nausea, bone pain
Treatment: Osteoporosis in postmenopausal women and men with osteoporosis;
treatment of glucocorticoid-induced osteoporosis
Nursing considerations: Take the drug in the morning with a full glass of plain water (not mineral water),
at least 30 minutes before any beverage, food, or medication and stay
upright for 30 minutes.
• Didronel
Desired effects: Slows normal and abnormal bone resorption; reduces bone formation and
bone turnover
Side effects: Hematological: elevated BUN and serum creatinine; increased or recurrent
bone pain, focal osteomalacia
Treatment: Paget’s disease of bone (oral), heterotopic ossification (oral), hypercalcemia of
malignancy in patients inadequately managed by diet or oral hydration
(parenteral); unlabeled use: treatment of postmenopausal osteoporosis and
prevention of early menopausal bone loss
Nursing implications: Administer with a full glass of water 2 hours before patient takes their
medication; monitor serum calcium levels before during and after therapy.
Ensure a 3-month rest period after treatment for Paget’s disease if retreatment is
required, and 7 days between treatments for hypercalcemia of malignancy;
ensure adequate vitamin days and calcium intake; provide comfort measures
if bone pain returns.
• Calcitonin
Desired effects: The calcitonins are polypeptide hormones secreted by the thyroid; human
calcitonin is a synthetic product classified as an orphan drug; salmon
calcitonin appears to be a chemically identical polypeptide but with greater
potency per milligram and longer duration; inhibits bone resorption; lowers
elevated serum calcium in children and excretion of filtered phosphate,
calcium, and sodium by the kidney
Side effects: Flushing of face, hand rash, nausea, vomiting, increased urinary frequency
Treatment: Human and salmon calcitonin are used in the treatment of Paget’s disease;
salmon calcitonin is used in the treatment of postmenopausal osteoporosis
in conjunction with adequate calcium and vitamin D intake to prevent loss of
bone mass; salmon calcitonin is used in the treatment of hypercalcemia as
emergency treatment.
Nursing implications: Assess for allergy to salmon calcitonin or fish products; inject doses of more
than 2 mL IM, not SC; use multiple injection sites; refrigerate nasal spray
until activated, then store at room temperature.
Note: Didronel can be administered IV or PO.
Use calcitonin cautiously with renal insufficiency, osteoporosis, and pernicious ane-mia. Also, keep parenteral calcium on hand in case of the development of hypocalcemictetany.
62
Drugs that Affect the Blood ◆ 63
DEFICIENCY ANEMIA
1. Anemia is defined as a decrease in erythrocyte number, size, or hemoglobin con-tent.
2. Causes of anemia include blood loss, hemolysis, bone marrow dysfunction, anddeficiencies of substances essential for hematopoiesis (red blood cell formationand maturation).
3. Most deficiency anemias result from a deficiency in vitamin B12, iron, or folicacid.
4. Iron-deficiency anemia is much more common than anemia due to deficiency ofvitamin B12 or folic acid.
◆ Drugs for Deficiency Anemia
Generic Name Trade Name
Epoetin alfa Epogen, ProcritTreatment: Erythropoietin is one endogenous factor controlling the rate of cell
production; a synthetic drug, epoetin alfa has been developed using
recombinant DNA technology; epoetin alfa is used to treat anemia caused
by reduction of endogenous erythropoietin production; causes include
end-stage renal disease, anemia caused by zidovudine, and anemia caused
by chemotherapy
Side effects: Seizures, hypertension, hypertensive encephalopathy
IRON-DEFICIENCY ANEMIA
1. Groups considered most frequently at risk for developing iron-deficiency anemiaare infants under 2 years of age, teenagers, pregnant women, and the very elderly.Pregnant teenagers are frequently at very high risk.
2. Iron deficiency manifests ultimately by the development of anemia, which is cor-rected by giving diets rich in absorbable iron and by providing iron supplementsin the form of ferrous sulfate or ferrous gluconate.
3. Iron deficiency can be caused by (1) chronic blood loss, such as a bleeding pepticulcer, hemorrhoids, parasites, or malignancy; (2) faulty iron absorption, iron-poordiet, or chronic GI disturbances such as diarrhea; and (3) increased iron require-ment that occurs in expanded blood volume as seen in infancy, adolescence, andpregnancy.
64 ◆ Chapter 6
Nursing Implications
1. Liquid iron preparations can stain teeth. The effect can be prevented by dilutingliquid preparation with juice or water, administering the iron through a straw orwith a dropper, and rinsing the mouth after administration.
2. In addition to medication, attention should be given to the amount of absorbableiron in foods. Liver, kidney, egg yolk, dried fruit, beans, nuts, raisins, green leafyvegetables, and fortified cereals rank highest in iron content.
3. Oral ferrous sulfate is the drug of choice for treating iron-deficiency anemia. Ironis best absorbed when the stomach is empty; however, under these conditions ittends to cause gastric irritation.
4. Sustained-release or enteric-coated iron preparations reduce gastrointestinal sideeffects by preventing rapid dissolution of iron; at the same time, however, they mayallow iron to bypass the jejunum, which is the most active site of iron absorption.
5. Side effects are dose-related, and smaller dosages have been suggested with theexpectation that the therapeutic program will be longer.
6. If the patient is not taking the oral iron supplement because of the side effects ofthe iron or it is not being absorbed (possibly as a result of malabsorption), theniron dextran may be administered parenterally (IM).
7. Clinical findings of iron-deficiency anemia are reflected in a variety of symptoms,including fatigue, anorexia, and pica, especially pagophagia (eating ice).
PERNICIOUS ANEMIA
1. The cause of pernicious anemia (also known as megaloblastic anemia) is a defi-ciency of vitamin B12.
2. Insufficient vitamin B12 in the diet is rarely a cause of deficiency. Potential causesfor poor absorption include regional enteritis and celiac disease (a malabsorptionsyndrome involving abnormalities in the intestinal villi).
3. Most frequently, the cause of pernicious anemia is impaired absorption of vitaminB12 secondary to lack of intrinsic factor. The principal causes of intrinsic factordeficiency are atrophy of gastric parietal cells and surgery of the stomach (partialor total gastrectomy).
4. It is important to note that hematologic effects of vitamin B12 deficiency can bereversed with B12 given parenterally (IM). When folic acid is administered in largeamounts, some of it can be activated independent of vitamin B12 and this will alsoreverse the hematologic effects of vitamin B12 deficiency.
5. Treatment of severe vitamin B12 deficiency involves the following: (1) IM injec-tions of vitamin B12 and folic acid (the folic acid accelerates recovery of hemato-logic deficits), (2) administration of 2–3 units of packed red blood cells (to correctanemia quickly), (3) transfusion of platelets (to suppress bleeding), and (4) therapywith antibiotics if infection has developed.
Drugs that Affect the Blood ◆ 65
6. When megaloblastic anemia (oversized erythroblasts appear in bone marrow andin the blood) occurs, it may be due to vitamin B12 deficiency or lack of folic acid;therefore, a definitive diagnosis must be made before treatment.
7. Two tests are particularly helpful for establishing a diagnosis of vitamin B12 de-ficiency: measurement of plasma vitamin B12 content (it will be low if B12 is notbeing absorbed), and the Schilling test, which measures vitamin B12 absorption.
8. The Schilling test is performed by administering a small dose of radioactive vitaminB12, after which the urine is monitored for the appearance of radioactivity. Ifthe urine remains free of radioactivity, one can conclude that vitamin B12 wasnot absorbed and absorption is impaired. The combination of plasma vitaminB12 measurement and the evidence of vitamin B12 malabsorption permits a cleardiagnosis of pernicious anemia and folic acid deficiency is ruled out.
Nursing Implications
1. Parenteral forms of cyanocobalamin can be administered by intramuscular or deepsubcutaneous injection.
2. Parenteral administration is required for all patients who are able to absorb oral vi-tamin B12. Patients unable to absorb vitamin B12 should be assessed for perniciousanemia, as described in the previous section.
3. Deficiency of vitamin B12 causes demyelination of neurons, primarily in the spinalcord and brain.
4. The neuronal injury produces paresthesias (tingling and numbness) of the handsand feet and a reduction in deep tendon reflexes.
5. Late-developing responses include loss of memory, mood changes, hallucinations,and psychosis.
6. If vitamin B12 deficiency is prolonged, neurologic damage can become permanent.
7. Vitamin B12 deficiency also prevents the bone marrow from forming leukocytes(white blood cells) and thrombocytes (platelets). Therefore, assessment for infec-tion and bleeding is a priority for patients with pernicious anemia.
8. Anemia may cause peripheral and cerebral hypoxia. Heart failure and dysrhyth-mias are the most frequent causes of death.
FOLIC ACID DEFICIENCY
1. Folic acid deficiency also causes megaloblastic anemia. Folic acid is necessaryfor DNA synthesis; without folic acid, DNA replication and cell division becomedisrupted.
2. In order to be usable, folic acid must be converted by vitamin B12 to an active form.As discussed before, however, when large amounts of folic acid (also known asfolate) are ingested, some of this folic acid can be activated via an alternativepathway—one that does not employ vitamin B12. Hence, even in the absence of
66 ◆ Chapter 6
vitamin B12, if sufficient amounts of folic acid are consumed, active folate will beavailable for DNA synthesis.
3. In contrast to vitamin B12, folic acid is not rigidly conserved; significant amountsare excreted every day. If the intake of folic acid was to significantly decreasewithin a few weeks (if body stores were already low), severe folic acid deficiencywould occur.
Nursing Implications
1. Folic acid deficiency has two principal causes: (1) low consumption of folic acid(especially as seen in alcoholics), and (2) malabsorption secondary to intestinaldisease.
2. The modality of treating folic acid deficiency should match the cause. If folic aciddeficiency is due to poor diet, the deficiency is corrected by dietary measures andnot by drugs.
3. Ingesting one fresh vegetable or one glass of fruit juice a day will usually correctthe deficiency.
4. In contrast, when folate deficiency is the result of malabsorption, diet alonewill not correct the deficiency, and a pharmaceutical preparation of folate isneeded.
ANTILIPEMIC AGENTS
The antilipemics are used to lower blood cholesterol.
◆ HMG-CoA Reductase Inhibitors (Statins)
Generic Name Trade Name
Atorvastatin LipitorFluvastatin LescolSimvastatin ZocorLovastatin MevacorRosuvastatin calcium CrestorPravastatin PravacholDesired effects: HMG-CoA reductase inhibitors inhibit the enzyme that catalyzes the
first step in the cholesterol synthesis pathway, resulting in a decrease
in serum cholesterol, serum LDL (which is associated with an
increased risk of coronary artery disease), and either an increase or
no change in serum HDL (which is associated with a decreased risk
of coronary artery disease).
Drugs that Affect the Blood ◆ 67
◆ HMG-CoA Reductase Inhibitors (Statins) (continued)
Generic Name Trade Name
Pravastatin (continued) PravacholSide effects: Headaches, blurred vision, dizziness, insomnia, flatulence, abdominal
pain, constipation, cataracts, and elevations of CPK and alkaline
phosphatase
Treatment: Adjuncts to dietary modification in the treatment of elevated total
cholesterol and LDL in patients with primary hypercholesterolemia
whose response to dietary restriction of saturated fat and cholesterol
and other pharmacologic measures has not been adequate: primary
prevention of coronary events (Lovastatin, Pravastin); secondary
prevention of CV events (Fluvastatin, Lovastatin, Simvastatin)
Nursing implications: Administer the drug at night; highest rates of cholesterol synthesis occur
between midnight and 5 A.M.; consult with a dietitian about
low-cholesterol diets; arrange for diet and exercise consultation;
arrange for periodic ophthalmologic examinations to check for
cataract development
◆ Bile-Acid Binding Sequestrants
Generic Name Trade Name
Cholestyramine Cholybar, QuestranColestipol ColestidColesevelam WelcholDesired effects: They bind bile acids in the intestine to form a complex that is excreted
in the feces; as a result cholesterol is lost, oxidized in the liver, and
serum cholesterol and LDL are lowered.
Side effects: Hematuria, dysuria, diuresis, constipation due to fecal impaction,
exacerbation of hemorrhoids, increased bleeding tendencies related
to vitamin K malabsorption deficiencies; decreased absorption of
fat-soluble vitamins; decreased serum levels or delayed absorption of
thiazide diuretics and digitalis; decreased absorption of other oral
drugs; administer them 1 hour before or 4–6 hours after colestipol.
Treatment: Adjunct therapy: reduction of elevated serum cholesterol in patients
with primary hypercholesterolemia (elevated LDL)
Nursing implications: Do not administer drug in dry form; mix in food (e.g., soup or cereal)
and add the prescribed 90 mL of liquid; stir until completely mixed;
make sure that patients swallow tablets whole; do not cut, crush, or
chew them; tablets should be taken with plenty of fluids
68 ◆ Chapter 6
◆ Fibric Acid Derivatives (Fibrates)
Generic Name Trade Name
Fenofibrate TricorGemfibrozil LopidDesired effects: Fibrates break down the particles that make up triglycerides; these drugs are
usually taken twice a day: 30 minutes before breakfast and before the
evening meal.
Side effects: Cardiac arrhythmias, angina, phlebitis, thrombophlebitis, rash, impotence,
decreased libido, flulike symptoms, myalgia, gastrointestinal discomfort,
aching muscles, sensitivity to sun, skin rashes
Treatment: Adjuncts to diet in treating adults with primary hypercholesterolemia and
hypertriglyceridemia
Nursing implications: Advise patients to take these drugs with meals; continue to follow a strict
dietary regimen and exercise program; arrange to have regular follow-up
visits with the health care provider, which will include blood tests.
◆ Cholesterol Absorption Inhibitor
Generic Name Trade Name
Ezetimibe ZetiaDesired effects: This cholesterol absorption inhibitor hinders the absorption of cholesterol
by the small intestine; this leads to decreased delivery of dietary
cholesterol to the liver, which will increase the clearance of cholesterol
from the blood and lead to a decrease in serum cholesterol.
Side effects: Headache, dizziness, fatigue, abdominal pain, myalgia, viral infection,
back pain
Treatment: Zetia is used as an adjunct to diet and exercise to lower cholesterol, LDL,
and Apo-B levels in patients with primary hypercholesterolemia as
monotherapy or in combination with an HMG-CoA reductase
inhibitor (statin); used in combination with atorvastatin or simvastatin for
the treatment of homozygous familial hypercholesterolemia as an
adjunct to other lipid-lowering therapy
Nursing implications: Monitor serum cholesterol, LDL, and triglycerides before starting treatment
and periodically during treatment; determine that the patient has been
on a low-cholesterol diet and exercise program for at least 2 weeks
before starting Zetia; help nursing mothers to find another method of
feeding their babies if this drug must be taken; it is not known if the
drug enters breast milk.
Drugs that Affect the Blood ◆ 69
GENERAL GUIDELINES FOR DRUG TREATMENT
1. Expert guidelines now recommend starting cholesterol-lowering drugs along witha diet and exercise regimen for the following groups:
a. People with LDL levels of 130 mg/dL or greater if they have existing heartdisease or risk factors that place them in equivalent danger. Such factors includediabetes or other disease that suggests atherosclerosis (such as peripheral arterydisease or blockage in the carotid artery). Their goal is to achieve an LDL levelof 100 mg/dL.
b. People with LDL cholesterol levels of 160 mg/dL or greater who have noexisting heart disease but have two or more risk factors. Their goal is an LDLlevel of 130 mg/dL.
c. People whose LDL is 190 mg/dL or over who have one or no risk factors. Theyshould strive for LDL levels of 160 mg/dL or less.
2. Evidence now strongly suggests that cholesterol-lowering drugs are improvingsurvival in heart attack patients. Experts now recommend that drug treatment betailored to raise or lower specific lipids, depending on the patient’s blood lipidlevels.
3. The body needs cholesterol for digesting dietary fats, making hormones, buildingcell walls, and other important processes, but too much circulating cholesterolcan injure arteries, especially the coronary arteries. This leads to accumulation ofcholesterol-laden plaque on vessel walls, a condition called atherosclerosis.
4. It is true that lowering cholesterol can benefit the heart. Cholesterol is criticallyimportant for every cell in the body, and lowering it too much may damage other or-gans, according to Dr. Beatrice Golomb, a cholesterol researcher at the Universityof California, San Diego. Dr. Golomb and other researchers are especially con-cerned about the brain, which makes up less than 4% of the body’s weight but con-tains 25% of its cholesterol. Dr. Golomb states that “Brain cells require cholesterolto communicate with each other.” This may explain why studies at the Universityof Pittsburgh and elsewhere have shown that people who take cholesterol-loweringdrugs have poorer memories and slower motor reflexes, and why men in earliercholesterol-lowering studies had fewer heart attacks but more fatal car accidents.
Chapter
7 Endocrine Drugs
DRUG THERAPY FOR TYPE II(NON-INSULIN-DEPENDENT) DIABETES MELLITUS
1. Non-insulin-dependent diabetes mellitus (NIDDM) is the most prevalent type ofdiabetes. Approximately 10 million Americans are known to have this disease.
2. NIDDM has two alternative names: type II diabetes mellitus and adult-onset dia-betes mellitus.
3. Patients with NIDDM can take oral hypoglycemic agents because some of thebeta cells (insulin-producing cells of the pancreas) can still produce insulin whenstimulated with these drugs.
DRUG THERAPY FOR TYPE I (INSULIN-DEPENDENT)DIABETES MELLITUS
1. Insulin-dependent diabetes mellitus (IDDM) accounts for about 10% of all dia-betes. Approximately 1 million Americans have this disorder.
2. IDDM is known by three alternative names: type I diabetes mellitus, juvenile-onset diabetes mellitus, and ketosis-prone diabetes mellitus. As a rule, IDDM
70
Endocrine Drugs ◆ 71
develops during childhood or adolescence. Onset of symptoms is usuallyabrupt.
3. The primary defect in IDDM is destruction of pancreatic beta cells (the cellsresponsible for insulin synthesis). When insulin is not available to carry sugar intothe cells, the body will then burn fat, producing ketones and acids. The client is ina state of hyperglycemia and may go into a state of ketoacidosis.
◆ Oral Medications for Type II Diabetes
Generic Name Trade Name (When to Take)
Drug classification Antidiabetic
Sulfonylureas
Mechanism of action: Stimulate
insulin release
Glyburide Micronase, DiaBeta (with meals)
Glipizide Glucotrol (30 minutes before meals)
Glimepiride Amaryl (with breakfast)
Tolbutamide Orinase (before breakfast)
Chlorpropamide Diabinese (before breakfast)
Acetohexamide Dymelor (Canada), Dymelor (before morning and evening meals)
Drug classification Antidiabetic,
Meglitinide
Mechanism of action: Stimulate
insulin release
Repaglinide Prandin (15 minutes before each meal)
Nateglinide Starlix (30 minutes before each meal)
Drug classification Antidiabetic
Metformin Glucophage (with meals)
Metformin Glucophage XL (with meals)
Drug classification Antidiabetic Alpha-glucosidase inhibitors
Mechanism of action: Limit carbohydrate absorption
Precose Acarbose (with first bite of a meal)
Glyset Miglitol (with first bite of a meal)
Drug classification
Thiazolidinedione:
Mechanism of action: Increases insulin sensitivity at insulin receptor
sites to lower blood glucose, decreases hepatic gluconeogenesis,
and increases insulin dependent muscle glucose uptake.
Rosiglitazone Avandia(with or without food)
Pioglitazone Actos (with or without food)
Clinical alert: Name confusion has occurred between DiaBeta (glyburide) and
Zebeta (bisoprolol), so use caution; Zebeta is a beta-selective
adrenergic blocking agent; assess the patient for signs and
symptoms of hyperosmolar coma, which are polyuria, polyphagia,
and severe dehydration.
Desired effect: Control blood glucose in non-insulin-dependent diabetics
Side effects: Hypoglycemia
Treatment: Non-insulin-dependent type II diabetes mellitus (NIDDM)
72 ◆ Chapter 7
NURSING IMPLICATIONS FOR TYPE II DIABETES MELLITUS
1. Transfer to insulin therapy during periods of stress (e.g., infection, surgery, ortrauma).
2. Consult with a dietitian to establish a weight loss program and dietary control asappropriate.
3. The diabetic teaching program should include details of the disease, dietary control,exercise, signs and symptoms of hypoglycemia and hyperglycemia, avoidance ofinfection, and good hygiene.
4. Provide good skin care to prevent breakdown.
5. Assess the patient for hyperosmolar nonketotic diabetic coma, as it is usuallya complication in patients with NIDDM. It is a state of profound dehydrationresulting from sustained hyperglycemia and diuresis if the client is unable to drinksufficient fluids to maintain proper fluid levels. Administer IV normal saline asprescribed by the physician.
6. When a patient with NIDDM is developing hyperosmolar hyperglycemic nonke-totic syndrome the only apparent signs and symptoms are diuresis and dehydration.
7. When a patient with IDDM develops ketoacidosis, there will be many apparentsigns and symptoms (e.g., nausea, vomiting, and Kussmaul’s breathing), whichbring the patient to physician attention before extreme dehydration can occur. Sucha protective mechanism is not present in type II diabetics.
Note: The reason for the absence of ketoacidosis in type II diabetes is not known.
NURSING IMPLICATIONS FOR TYPE I DIABETES MELLITUS
1. The intent is to reduce blood glucose levels by facilitating metabolism of glucoseand to prevent excessive breakdown of protein.
2. The main side effects are hypoglycemia and ketoacidosis. Symptoms of ketoaci-dosis include polyuria, polyphagia, dehydration, fruity breath, and Kussmaul’sbreathing.
3. Treatment is with insulin administered SC with the needle at a 90-degree angle; noaspiration is necessary. Regular insulin is clear and long-lasting insulin is cloudy;the bottle of insulin must be rolled in the hands to mix well before administration.If regular and long-lasting insulin are to be administered in combination, theregular insulin is drawn into the syringe first. Use only an insulin syringe whenadministering insulin.
DIAGNOSIS OF TYPE I DIABETES MELLITUS
1. Glycosylated hemoglobin (A1c) is a diagnostic test for blood glucose levelover a period of 2–3 months. If the blood glucose level has not been
Endocrine Drugs ◆ 73
TABLE 7–1 ◆ Hypoglycemic Agents (IV and SC)
Time of Peak of Duration Route andType of Insulin Onset Action of Action Appearance
Rapid-actingInsulin Lispro (Humalog) 5 min 0.5–1.5 3–4 h Clear (SC and IV)
Insulin Aspart (NovoLog) 5–10 min 1–3 h Clear (SC and IV)
Short-actingRegular (Humulin R, Novolin R) 30–60 min 2–3 h 6–12 h Clear (SC)
Intermediate-actingNPH (Humulin N, Novolin N) 1–2 h 8–12 h 18–24 h Cloudy (SC)
Lente (Humulin L, Novolin L) 1–2 h 8–12 h 10–16 h Cloudy (SO)
Long-actingUltralente (Humulin U) 4–8 h 10–30 h 30–36 h Cloudy (SC)
Insulin glargine (Lantus) 60 min None 24 h Clear (SC)
Premixed insulinsNPH/regular 70%/30% Cloudy (SC)
Novolin/regular 70%/30% Cloudy (SC)
NPH/regular 50%/50% Cloudy (SC)
Lispro/regular 75%/25% Cloudy (SC)
Ultralenta/regular 70%/30% Cloudy (SC)
Premixed insulin onset, peak
and duration depends on
type of insulin mixture
Notes: Humalog is faster-acting than Humulin R insulin. These two types of insulin have similar sounding names; therefore,
care must be taken so the correct drug is administered.
Insulin lispro (Humalog) and Insulin aspart (NovoLog) should not be used in an insulin infusion pump and cannot be mixed
with other insulin products.
Humalog is administered 15 minutes before meals and regular insulin is administered 30–60 minutes before meals. Regular
insulin should not be mixed with zinc suspension insulin because of interference with its actions.
controlled in the preceding 2–3 months, the hemoglobin A1c level will beincreased.
2. Home glucose monitoring involves obtaining a drop of capillary blood from afinger with a sterile lancet. The blood is placed on a semi-permeable membranethat contains a reagent. The amount of blood glucose in milligrams can be readwith the use of a glucose meter (e.g., Acu-Chek, Glucometer).
3. Test urine for ketones (type I DM) when blood glucose levels are above 240 mg/100 mL in home care situations; in the hospital a blood test is used to detectketones.
4. The fasting blood sugar test is used to diagnose diabetes mellitus. Two or morefasting blood glucose levels above 126 mg/100 mL are diagnostic of diabetesmellitus.
74 ◆ Chapter 7
HYPOGLYCEMIA, HYPERGLYCEMIA, AND KETOACIDOSIS
1. A hypoglycemic reaction occurs when (1) more insulin is administered than isneeded for glucose metabolism; (2) the patient fails to eat the recommended num-ber of calories; or (3) the patient exercises more than usual.
2. Hypoglycemic reactions usually occur during insulin peak time. The person maybecome nervous, trembling, confused, sweaty, weak, and irritable, and may com-plain of a headache with a blood sugar level <60 mg/dL. Giving sugar orallyor glucose intravenously increases the utilization of insulin, and the symptomsusually disappear almost immediately.
3. Hyperglycemia occurs when the amount of insulin present is inadequate, and sugarcannot be metabolized and fat catabolism occurs. The use of fatty acids (ketones)for energy causes ketoacidosis (diabetic ketoacidosis that can lead to diabeticcoma).
4. Signs and symptoms of hyperglycemia include polyuria, polydipsia, and polypha-gia. Other symptoms may include blurred vision, fatigue, and dry mouth. To treat,regular insulin is given IV or SC.
5. Signs and symptoms of diabetic ketoacidosis include extreme thirst, polyuria,polydipsia, polyphagia, fruity breath odor, Kussmaul’s breathing (deep, rapid,labored breathing), rapid thready pulse, dry mucous membranes, poor skin turgor,and nausea and vomiting with a blood sugar level >400 mg/100 dL. If ketoacidosisis suspected, consult a physician immediately.
NURSING IMPLICATIONS FOR TYPE I DIABETES MELLITUS
1. Treatment of diabetics must be very individualized because patients responddifferently when given the same amount and same kind of insulin. Some patientsbecome hypoglycemic with a blood sugar of <70 mg/100 dL, but may not havesymptoms of hypoglycemia.
2. The average normal blood glucose value according to the American DiabetesAssociation for adults is 70–120 mg/100 mL.
3. Thiazide diuretics, acute ingestion of alcohol, steroid preparations, thyroid prepa-rations, estrogen, smoking, and rifampin may increase blood glucose, thereforeincreasing insulin requirements.
4. Anabolic steroids (e.g., testosterone), guanethidine, tricyclic antidepressants(e.g., Elavil) antidepressants (e.g., Prozac), MAOIs (e.g., Parnate), salicylates,phenylbutazone, and oral anticoagulants (e.g., Coumadin) may decrease insulinrequirements.
5. Carefully assess the patient for symptoms indicative of insulin shock or diabeticacidosis.
6. Check glucose as ordered by a physician.
Endocrine Drugs ◆ 75
7. Administer insulin SC or oral hypoglycemic agents as ordered; know thetime, peak, onset, and duration of action for each specific type of insulin youadminister.
8. Explain dietary restrictions to the patient, in addition to the need for a steady,consistent level of exercise on a daily basis.
9. Patients with diabetes must understand the disease, its possible complications,and treatment.
10. Be certain that the patient understands the need for good hygiene and proper careof the feet.
11. Exercise may cause hypoglycemic reactions because sugar outside the cell iscarried into the cell for energy production.
12. Stress may cause hyperglycemia because stress increases steroid and epinephrineproduction. Both of these increase glucose levels.
13. Assess the patient’s ability to understand dosage and administration of insulinSC or oral antidiabetic agents, as well as proper injection technique.
14. Explain the signs of insulin shock and diabetic ketoacidosis, and what to do ifeither of these conditions should develop.
DRUGS THAT MAY INCREASE BLOOD GLUCOSE LEVELS ANDINSULIN REQUIREMENTS
These may increase insulin requirements: glucagons, Bronkosol, Hyperstat, epinephrine,synthetic catecholamines, Alupent, Proventil, thiazide diuretics, Brethine, steroids, thy-roid preparations, Ventolin, estrogen, rifampin, and Diuril. Consuming alcohol and smok-ing will also increase insulin requirements.
DRUGS THAT MAY DECREASE INSULIN REQUIREMENTS
These may decrease insulin requirements: anabolic steroids (e.g., testosterone), tricyclicantidepressants (e.g., Elavil, Prozac), MAOIs (e.g., Parnate), salicylates, phenylbutazone,and anticoagulants (e.g., Coumadin).
DRUG THERAPY FOR THYROID DISORDERS
1. Thyroid hormones have profound effects on metabolism, cardiac function,growth, and development. These hormones stimulate the metabolic rate of mostcells.
2. The thyroid gland produces two active hormones: triiodothyronine (T3) andthyroxine (T4). The preparations of T3 and T4 employed clinically aresynthetic.
76 ◆ Chapter 7
◆ Agents Used to Treat Hypothyroidism (Myxedema)
Generic Name Trade Name
Liothyronine (T3) CytomelLevothyroxine (T4) SynthroidLiotrix (T3 and T4) ThyrolarDesiccated thyroid Armour Thyroid, S-P-T (this thyroid hormone preparation
contains T3 and T4 in their natural state and ratio)
Desired effects: Increases metabolic rate of body tissues, thereby increasing oxygen
consumption, respiration, and heart rate; metabolism of fat, protein,
and carbohydrate; and rates of growth and maturation
Side effects: Irritability, nervousness, insomnia, tachycardia, dysrhythmias, and weight
loss
Treatment: Hypothyroidism, thyroid hormone replacement
Note: Synthroid interacts with many drugs (e.g., chloramphenicol, colestipol, norepinephrine, and anticoagulants).
NURSING IMPLICATIONS FOR HYPOTHYROIDISM
1. Provide a high-bulk diet and encourage activity to combat constipation and pro-mote weight loss.
2. To prevent myxedema coma, tell the patient to continue the course of thyroidmedication even if symptoms subside.
3. After thyroid replacement therapy begins, watch for symptoms of hyperthyroidism,such as restlessness, sweating, and excessive weight loss.
4. Check frequently for signs of decreasing cardiac output such as falling urine output.
AGENTS USED TO TREAT HYPERTHYROIDISM
There are three major categories of thyroid inhibitors: thioamide derivatives (propyl-thiouracil, methimazole), iodides, and radioactive iodine. In addition to these agents,beta blockers (e.g., propranolol [Inderal]) can be used to treat hyperthyroid patients.Propranolol is used to decrease the symptoms of hyperthyroidism.
TREATMENT OF HYPERPARATHYROIDISM
1. A large volume of IV fluid is administered along with Lasix, forcing the excretionof sodium and calcium.
2. Calcitonin may be administered in life-threatening circumstances to decrease boneresorption of blood calcium; this will decrease serum calcium levels and increasedeposition of calcium in bones, effects opposite of those of parathyroid hormone.
Endocrine Drugs ◆ 77
◆ Thioamide Derivatives Used for Hyperthyroidism(Graves’ Disease )
Generic Name Trade Name
Methimazole TapazolePropylthiouracil • Propyl-Thyracil (Canada), PTU
Treatment: PTU or Tapazole can be administered alone to control hyperthyroidism,
employed as adjuncts to radiation therapy, or be given to suppress
thyroid hormone synthesis in preparation for thyroid surgery (subtotal
thyroidectomy)
Desired effect: They suppress thyroid hormone synthesis; PTU or Tapazole do not
destroy existing stores of the hormone; instead, they prevent thyroid
hormone synthesis.
Side effects: Agranulocytosis: this reaction is rare and usually occurs during the first
2 months of therapy; agranulocytosis is an acute disease of the white
blood cells in which the count drops to extremely low levels;
hypothyroidism will occur with excessive dosing with PTU or
Tapazole, which may cause the patient to enter a hypothyroid state; if
this occurs, the dosage is reduced.
Nursing implications: PTU and Tapazole cross the placenta and can cause neonatal
hypothyroidism and goiter; these drugs must be used judiciously
during pregnancy to minimize effects on the fetus, and the dosage
kept as low as possible; these drugs enter breast milk; therefore, a
patient on PTU or Tapazole should be advised not to breast-feed.
TREATMENT OF HYPOPARATHYROIDISM
Because calcium absorption from the small intestine requires the presence of vitaminD, treatment includes vitamin D and calcium. Acute life-threatening tetany requiresimmediate IV administration of calcium gluconate or calcium chloride to raise serumcalcium levels.
RADIOACTIVE IODINE (131I)
1. 131I, a radioactive isotope, is a stable form of iodine that emits a combination ofbeta particles and gamma rays.
2. 131I can be used to destroy thyroid tissue in patients with hyperthyroidism or cancerof the thyroid. The objective is to produce clinical remission without causingcomplete destruction of the gland.
3. The nurse must use gloves when handling urine containers and flush the toiletthree times.
78 ◆ Chapter 7
◆ Nonradioactive Iodide Products (Preoperative Medications)
Generic Name Trade Name
Strong iodine solution Lugol’s solutionPotassium iodide Potassium iodide solution (SSKI)Intravenous
sodium iodideNo commonly used trade name
Treatment: Lugol’s solution and SSKI are given to hyperthyroid individuals to
suppress thyroid function in preparation for thyroid surgery; initial
effects of SSKI or Lugol’s solution begin within the first 24 hours;
peak effects develop in 10–15 days; in most cases, plasma levels of
thyroid hormone are reduced with PTU prior to therapy with iodine;
iodine solution (together with PTU) is then administered for the last
10 days prior to subtotal thyroidectomy
Side effects with
nursing
implications:
Brassy taste, burning sensation in the mouth and throat, soreness of
teeth and gums; sodium iodide (IV) is employed for acute
management of thyrotoxic crisis, which may occur during or after
surgery on the thyroid gland; benefits are derived from the ability of
high concentrations of iodide to rapidly suppress thyroid hormone
release; in treatment of thyrotoxicosis (a toxic condition due to
hyperactivity of the thyroid gland), sodium iodide is used in
combination with propylthiouracil and propranolol (Inderal);
although sodium iodide rarely causes adverse side effects, severe
hypersensitivity reactions have occurred; the most serious of these is
edema of the larynx, and death can occur.
4. The advantages of 131I treatment are: (1) low cost; (2) patients are spared the risk,discomfort, and expense of thyroid surgery; (3) death from 131I treatment has neveroccurred; and (4) no tissue other than the thyroid is injured.
5. Disadvantages of 131I treatment are that it takes several months to achieve maxi-mum effect, and that treatment is associated with a significant incidence of delayedhypothyroidism.
6. Patients over age 30 may be candidates for 131I therapy. 131I is also indicated forthose who have not responded to antithyroid drugs or to subtotal thyroidectomy.
7. Children are not considered good candidates because the rate of delayed hypothy-roidism is higher in children than in adults.
8. 131I is contraindicated in pregnancy and lactation. Exposure of the fetus to 131I afterthe first trimester may damage the immature thyroid, and exposure to radiation atany point in fetal life carries a risk of generalized developmental harm.
9. Since 131I enters breast milk, women receiving this agent should not breast-feed.
Endocrine Drugs ◆ 79
PAGET’S DISEASE
Paget’s disease is a slowly progressive metabolic bone disease characterized by an initialphase of excessive bone resorption (osteoclastic phase), followed by a reactive phase ofexcessive abnormal bone formation (osteoblastic phase). The new bone structure, whichis fragile and weak, causes painful deformities of both external contour and internalstructure. Paget’s disease usually localizes in one or several areas of the skeleton (mostfrequently the lower torso), but occasionally skeletal deformity is widely distributed. Itcan be fatal, particularly when it is associated with congestive heart failure (widespreaddisease creates a continuous need for high cardiac output).
Drugs used to treat Paget’s disease include etidronate (Didronel), which slows nor-mal and abnormal bone formation and decreases serum calcium levels. Human calcitoninis also used to treat Paget’s disease; it is a synthetic product that inhibits bone resorption,lowers elevated serum calcium in patients with Paget’s disease, and increases removalof phosphate, calcium, and sodium by the kidney.
CONTRACEPTIVE AGENTS
ESTROGEN AND PROGESTINS
1. Estrogen and progestins are hormones that promote the maturation and activityof female reproductive organs.
2. In addition, these hormones promote development of secondary sexual charac-teristics in females.
3. The principal endogenous estrogen is estradiol.
4. The major progestational hormone is progesterone.
5. Both hormones are produced by the ovaries.
6. During pregnancy, large amounts are also produced by the placenta.
7. Clinical application of the female sex hormones falls into two major categories:contraceptive and noncontraceptive use.
8. For the estrogens, these applications include treatment of menopausal symptoms,osteoporosis, prostatic carcinoma, and carcinoma of the breast.
9. For the progestins, the principal noncontraceptive indications are amenor-rhea, dysfunctional uterine bleeding, endometrial carcinoma, and endome-triosis.
10. The use of estrogen and progestin for contraception is presented in the last partof this chapter.
11. Estrogen replacement therapy for postmenopausal women is contro-versial.
80 ◆ Chapter 7
ORAL CONTRACEPTIVE AGENTS
1. Oral contraceptives (OCs) are among the most effective forms of birth control.
2. There are two principal categories of oral contraceptives: those that containboth estrogen and a progestin, known as combination oral contraceptives (COs),and those that contain only progestin, known as “minipills” or progestin-onlypills.
3. Of the two groups, the combination pills are by far the most widely used. COs havebecome one of the most widely prescribed families of drugs, and they are nearly100% effective, making them one of the most effective forms of birth controlavailable.
4. The COs of have three subgroups: monophasic, biphasic, and triphasic.
5. In a monophasic regimen, the daily estrogen and progestin dosage remains constantthroughout the monthly cycle of use.
6. In a biphasic regimen, the estrogen dosage remains constant, but the progestindosage is increased during the second half of the cycle.
7. In a triphasic regimen, the progestin dosage changes for each phase of the cycle;in one segment, the estrogen dosage varies as well.
◆ Estrogen-Containing Preparations
Generic Name Trade Name Route Indications
Estrone Theelin Aqueous IM Female hypogonadism, prostate
cancer
Estropipate Ogen PO, vaginal cream Atrophic vaginitis, female
hypogonadism, prostate cancer
Conjugated estrogen Premarin PO Menopausal symptoms
Estradiol Estratab, Menest PO, vaginal cream Menopausal symptoms, female
hypogonadism, prostate cancer
Estradiol valerate Delestrogen Transdermal Menopausal symptoms, female
hypogonadism, prostate cancer
Diethylstilbestrol(DES)
No trade name PO, IV Breast cancer, prostate cancer
Desired effect: In postmenopausal women, estrogen replacement decreases bone loss and
reduces the incidence of fracture by increasing calcium absorption; however,
there must be pressure on long bones for calcium to be absorbed.
Side effects: Thromboembolic and thrombotic disease, hypertension, photosensitivity,
peripheral edema, intolerance to contact lenses.
There is no concrete evidence of birth defects related to estrogen or
progesterone when taken in small amounts during pregnancy.
Endocrine Drugs ◆ 81
◆ Estrogen-Containing Preparations (continued)
Generic Name Trade Name Route Indications
Side effects
(continued)
Progesterone is used to treat luteal phase defects in patients undergoing
infertility treatment; research has shown that a large number of patients have
continued to take oral contraceptives for sometimes months after conception
with no documented increase in congenital anomalies despite exposure to
both ethinyl estradiol and different progestins.
Diethylstilbestrol (DES) (a synthetic preparation possessing estrogenic
properties that is several times more potent than natural estrogens and may
be given orally) is used therapeutically in the treatment of menopausal
disturbances and other disorders due to estrogen deficiency. DES may cause
vaginal and cervical cancer in women who were exposed to it during fetal
life (i.e., women whose mothers took DES during pregnancy).
Note: Estraderm is available in a transdermal patch formulation. The patch is applied to the skin (not the breast), allowing
estrogen to be absorbed through the skin and then directly into the bloodstream. When compared with oral administration,
the patches have a significant advantage: the serum level of estrogen produced by the patches more closely resembles
premenopausal estrogen levels than do the serum levels produced by oral estrogens.
◆ Progestin-Containing Preparations
Generic Name Trade Name Route Indication
Progesterone No commonly used trade name IM Amenorrhea, dysfunctional
uterine bleeding
Megestrol acetate Megace PO Breast and endometrial cancer
Medroxyprogesterone Depo-Provera IM Amenorrhea, endometriosis,
endometrial cancer,
dysfunctional uterine
bleeding
Desired effects: Progesterone and Megace transform proliferative endometrium into secretary
endometrium; inhibit the secretion of pituitary gonadotropins, which prevents
follicular maturation and ovulation; inhibit spontaneous uterine contractions.
The mechanism of Megace’s antineoplastic activity is unknown, but may be due
to a pituitary-mediated anti-luteinizing effect.
Side effects: Sudden partial or complete loss of vision, proptosis, diplopia, migraine,
dizziness, thrombophlebitis, cerebrovascular disorders, retinal thrombosis,
pulmonary embolism, breakthrough bleeding, spotting, change in menstrual
flow, amenorrhea, dysfunctional uterine bleeding.
Treatment: Progesterone and Depo-Provera are used to treat dysfunctional uterine bleeding
that occurs when progesterone levels are insufficient to balance the stimulatory
influence of estrogen on the endometrium.
(continued)
82 ◆ Chapter 7
◆ Progestin-Containing Preparations (continued)
Generic Name Trade Name Route Indication
Treatment (continued) In the absence of sufficient progesterone, estrogen puts the endometrium in a
state of continuous proliferation.
Since progesterone is unavailable to induce monthly endometrial breakdown, the
excessively proliferative endometrium undergoes spontaneous sloughing at
irregular intervals. Irregular breakdown of the endometrium can result in
periodic episodes of severe menstrual bleeding.
Treatment has two objectives: (1) the initial goal is cessation of hemorrhage, and
(2) the long-term goal is to establish a regular monthly cycle.
Nursing implications: Educate patients that the administration of progestins in high doses during the first
4 months of pregnancy has been associated with an increased incidence of
birth defects (limb reductions, heart defects, and masculinization of the female
fetus); therefore, use of progestins during early pregnancy is not
recommended; women who become pregnant while taking progestin should
be apprised of the potential risk to the fetus; patients should be told to report
any episode of abnormal vaginal bleeding.
Note: Depo-Provera provides three or more months of contraceptive protection.
◆ Other Oral Contraceptives
Generic Name Trade Name
Combination OCsMonophasic
No generic name Lo-OvralNo generic name Ortho-CeptIntravenous sodium iodide Ovcon 50Triphasic
No generic name Ortho-Novum 7/7/7No generic name YasminNo generic name LevliteNo generic name AvianeProgestin-only OCsTriphasic
No generic name Nor-Q.D.
Endocrine Drugs ◆ 83
NURSING IMPLICATIONS OF ORAL CONTRACEPTIVES
1. Combination OCs have been associated with venous and arterial thromboem-bolism, pulmonary embolism, myocardial infarction, and thrombotic stroke.
2. Thrombotic disorders are caused by the estrogen component of combinationOCs, not by the progestin component.
3. The risk of thromboembolic phenomena from OCs is increased in the presence ofother risk factors, especially heavy smoking and a history of thromboembolism.
4. The incidence of hypertension among OC users is three to six times greater thanthat among nonusers.
5. Oral contraceptives elevate blood pressure by increasing blood levels of bothangiotensin (a potent vasoconstrictor) and aldosterone (a hormone that promotessalt and water retention).
6. The risk of hypertension increases with age and with duration of OC use.
7. The risk of cancer from OCs appears to be extremely low.
8. Birth defects can be produced by the mother’s use of estrogen and progestin.
9. By inducing endometrial regression, OCs may decrease or eliminate menstrualflow during the initial months of use. Bleeding and spotting may occur, but ifbleeding irregularity persists, the possibility of malignancy should be investi-gated.
10. Because of their carcinogenic and teratogenic actions, OCs are contraindicatedfor use during pregnancy.
11. Pregnancy should be ruled out prior to initiation of OC therapy.
12. If pregnancy occurs during OC use, drug administration should cease immedi-ately. OCs enter breast milk and also act to reduce milk production. Therefore,OCs should not be taken by women who are breast-feeding.
13. The incidence of twin births is increased in women who become pregnant shortlyafter discontinuing OCs.
14. Oral contraceptives can elevate plasma glucose levels. Glucose intolerance ismost likely in patients who are diabetics.
15. Progestin-only OCs (also known as “minipills”) contain progestin but have noestrogen. Because they lack estrogen, minipills do not cause thromboembolicdisorders, but have most of the other adverse effects associated with combinationOCs.
16. Unfortunately, although somewhat safer than combination OCs, the progestin-only preparations are less effective and cause more menstrual irregularity, in-cluding breakthrough bleeding, spotting, amenorrhea, inconsistent cycle length,variation in the blood volume, and duration of monthly blood flow.
17. Make patients aware of the following guidelines in the event of missed pills:(1) if one pill is missed, take it as soon as remembered, with the next pill taken
84 ◆ Chapter 7
as scheduled; (2) if two pills are missed, take one as soon as remembered, dis-card the other pill, and take the next pill as originally scheduled; (3) if threepills are missed, administration should be discontinued and use should not beresumed until menstruation occurs or until pregnancy has been ruled out. Pro-gestins are teratogenic and therefore must not be taken if there is any possibility ofconception.
OTHER TYPES OF CONTRACEPTIVES
DEPOT MEDROXYPROGESTERONE ACETATE
1. Following a single IM injection of medroxyprogesterone acetate (MPA; Depo-Provera), highly effective contraception for 3 or more months is provided.
2. Injections of 150 mg are repeated every 3 months to provide continuous protection.
3. Adverse effects of MPA are similar to those seen with other progestins.
EMERGENCY POSTCOITAL CONTRACEPTION
1. Postcoital contraceptives, also known as “morning-after” pills, can prevent preg-nancy when taken following intercourse.
2. To be effective, these drugs should be taken no later than 72 hours after coitus.
3. Because their side effects can be intense, postcoital contraceptives are not consid-ered substitutes for traditional methods of birth control.
DRUG THERAPY FOR INFERTILITY
1. The majority of drugs used to increase fertility are directed at improving repro-ductive function in females.
◆ Postcoital Contraceptives
Generic Name Trade Name
Ethinyl estradiol/norgestrel OvralMifepristone RU 486Desired effect: Prevention of pregnancy by the estrogen in Ovral and RU 486 is used
for postcoital contraception and for termination of early pregnancy
(abortion)
Side effects: Thromboembolism, stroke, pulmonary embolism, myocardial infarction,
anorexia, nausea, vomiting
Endocrine Drugs ◆ 85
◆ Agents Used to Treat Infertility
Generic Name Trade Name
Clomiphene ClomidMenotropins PergonalBromocriptine ParlodelDanazol DanocrineDesired effects: 1. Clomiphene—promotes follicular maturation and ovulation
2. Menotropins—promote follicular maturation and ovulation
3. Bromocriptine—corrects amenorrhea and infertility associated with excessive
prolactin secretion
4. Danazol—treats endometriosis and associated infertility
Side effects: Clomid: hot flashes, nausea, bloating, and breast engorgement
Pergonal: sudden enlargement of the ovaries
Danocrine: deepening of the voice and growth of facial hair
2. Drugs can increase female fertility by helping promote the following: (1) matura-tion of ovarian follicles, (2) ovulation, (3) production of favorable cervical mucus,(4) control of endometriosis, and (5) reduction of excessive prolactin levels. Theability of drugs to increase fertility in males is limited. In some cases, therapy mayimprove semen and sperm production.
UTERINE STIMULANTS
1. Uterine contractions can be intensified or diminished with drugs.
2. Drugs that stimulate contractions are known as oxytocics (drugs that inhibit con-tractions are called tocolytics).
3. There are three types of uterine stimulants:
a. Oxytocin: the principal indication for oxytocin is induction of labor.
b. Prostaglandins (e.g., dinoprostone): these are primarily used for abortion.
c. Ergot alkaloids (oxytocic agents): these are primarily used to control postpar-tum bleeding. They are also used to control bleeding after abortion.
◆ Uterine Stimulants
Generic Name Trade Name
Oxytocin PitocinErgonovine Ergotrate
(continued)
86 ◆ Chapter 7
◆ Uterine Stimulants (continued)
Generic Name Trade Name
Methylergonovine (ergot alkaloid) MethergineDesired effect: Pitocin is used to increase the force, frequency, and duration of
uterine contractions; the primary therapeutic use of oxytocin is
induction of labor near term.
Ergotrate and Methergine are used to control bleeding after
delivery of the placenta and to control bleeding after abortion.
Side effects: Pitocin: cardiac arrhythmias, hypertension, subarachnoid
hemorrhage, postpartum hemorrhage, uterine rupture, uterine
hypertonicity; a most serious but rare side effect is water
intoxication, with possible seizures, coma, and maternal
death.
Ergotrate and Methergine: dizziness, headache, transient
hypertension, palpitations, chest pain, nausea, vomiting
Nursing implications: During oxytocin infusion, constant monitoring is required; the
mother should be monitored for uterine contractility
(frequency, duration, and intensity), blood pressure, pulse
rate and rhythm.
In the event of significant maternal or fetal distress, the infusion
should be stopped; this will cause contractions to diminish
rapidly; complications that usually require interruption of the
infusion are (1) elevation of resting uterine pressure above
15–25 mm Hg, (2) contractions that persist for more than
1 minute, (3) contractions that occur more often than every
2–3 minutes, and (4) pronounced alteration in fetal heart
rate or rhythm.
Ergot alkaloids are contraindicated for women who are pregnant,
hypertensive, or hypersensitive to these drugs; ergot alkaloids
are also contraindicated for induction of labor and for use in
the presence of threatened or ongoing spontaneous abortion.
PROSTAGLANDINS
1. Prostaglandins are synthesized in all tissues of the body, where they act as localhormones.
2. Prostaglandin, like oxytocin, can increase the force, frequency, and duration ofuterine contractions.
3. Prostaglandins are used to induce abortion.
4. Dinoprost, tromethamine, and dinoprostone are prostaglandins that are used toinduce abortion during the second trimester.
5. Side effects include headache, dizziness, hypotension, nausea, vomiting, diarrhea,leg cramps, and joint swelling.
Endocrine Drugs ◆ 87
UTERINE RELAXANTS
Uterine relaxants (tocolytics) are given to prevent premature delivery (i.e., delivery priorto the 37th week of gestation).
◆ Uterine Relaxants
Generic Name Trade Name
Ritodrine YutoparTreatment: Suppression of preterm labor
Side effects: Pulmonary edema, tachycardia, hypotension, hyperglycemia
◆ Drug Therapy for Erectile Dysfunction
Generic Name Trade Name
Sildenafil citrate ViagraTadalafil CialisVardenafil LevitraDesired effect: Penile erection
Side effects: Headache, abnormal vision, dizziness, nasal congestion, dyspepsia,
diarrhea, urinary tract infection, rash
Note: Medical help is needed immediately for erection that lasts more than 4 hours. Priapism must be treated as soon as
possible or permanent damage can be done to the penis, including the inability to have erections.
Chapter
8 Drugs for Inflammatoryand Allergic Disorders
NONSTEROIDAL ANTI-INFLAMMATORY DRUGS
1. The nonsteroidal anti-inflammatory drugs (NSAIDs) are a large and commonlyprescribed family of drugs.
2. These drugs are the mainstay of treatment for inflammatory disorders (e.g., arthri-tis) and are used widely to relieve mild to moderate pain, suppress fever, andrelieve symptoms of primary dysmenorrhea.
3. Aspirin belongs to a chemical family known as the salicylates and is also knownas acetylsalicylic acid (ASA).
4. Aspirin can be used as an anticoagulant because it suppresses platelet aggregationand can decrease prothrombin production.
5. Reye’s syndrome is a rare but serious illness of childhood that has a mortality rateof 20–30%. Epidemiological data suggest a relationship between Reye’s syndromeand use of aspirin by children who have influenza or chickenpox; however, a directlink has not been established. Because of the possible relationship between aspirinand the development of Reye’s syndrome, it is recommended that aspirin and otherNSAIDs be avoided by children and teenagers suspected of having influenza orchickenpox.
88
Drugs for Inflammatory and Allergic Disorders ◆ 89
◆ Nonsteroidal Anti-Inflammatory Drugs
Generic Name Trade Name
Aspirin Ecotrin, Bayer, others
Diflunisal DolobidIbuprofen Motrin, Advil, others
Indomethacin IndocinKetorolac ToradolNaproxen sodium Anaprox, AleveCelecoxib CelebrexEtoricoxib ArcoxiaValdecoxib BextraDesired effects: Celebrex and Bextra: Analgesic and anti-inflammatory activities related to
inhabitation of the COX-2 enzyme, which is activated in inflammation
to cause the signs and symptoms associated with inflammation
Side effects with nursing
implications:
Aspirin: Gastric distress, nausea, GI bleeding, gastric ulceration, and
Reye’s syndrome; aspirin is contraindicated in patients with peptic
ulcer disease, bleeding disorders (e.g., hemophilia), vitamin K
deficiency, hypoprothrombinemia, and hypersensitivity to aspirin itself
or other NSAIDs
All NSAIDs may cause gastric irritation.
Take these drugs with food or after meals.
All of these drugs decrease renal flow and may cause renal failure.
In addition, aspirin should be used with extreme caution by pregnant
women and by children who have chickenpox or influenza; it should
be used with caution when treating the elderly.
Other NSAIDs: Adverse effects are minimal; these drugs produce less
GI disturbance and gastric bleeding, and cause less inhibition of
platelet aggregation than aspirin; all NSAIDs decrease renal blood
flow and may cause renal failure as well as the following hematologic
disorders: neutropenia, eosinophilia, leukopenia, pancytopenia,
thrombocytopenia, agranulocytosis, granulocytopenia, aplastic anemia,
decreased hemoglobin or hematocrit, bone marrow depression,
menorrhagia.
Note that the COX-2 inhibitors Celebrex and Bextra are still on themarket but Vioxx, also a COX-2 inhibitor, has been removed fromthe market due to severe side effects.
Treatment: All NSAIDs suppress inflammation, reduce fever, and relieve mild to
moderate pain; they relieve primary dysmenorrhea; they are used to
treat arthritis, tendonitis, and bursitis.
Clinical alert: Name confusion has occurred between Celebrex (celecoxib) and
Celexa (citalopram), Xanax (alprazolam), and Cerebyx
(fosphenytoin); use caution.
Note: Indocin has some serious side effects, including seizures, depression, psychosis, GI ulcerations, and hemorrhage.
90 ◆ Chapter 8
◆ Acetaminophen
Generic Name Trade Name
Acetaminophen Tylenol, others
Treatment: Relief of pain and fever in patients who cannot tolerate the
side effects of aspirin (e.g., patients with bleeding disorders or
peptic ulcers); because there is no association with Reye’s
syndrome, acetaminophen is preferred to aspirin for use by children
suspected of having chickenpox or influenza.
Side effects: Side effects are rare at therapeutic levels; the risk of liver injury is
increased in chronic alcoholics.
Nursing implications: Acetaminophen does not cause gastric ulcers or gastric bleeding;
it does not inhibit platelet aggregation, decrease renal
blood flow, or cause renal failure (as seen with NSAIDs).
GLUCOCORTICOIDS USED IN NONENDOCRINE DISEASES
1. Glucocorticoids are used to treat both endocrine and nonendocrine disorders.
2. Nonendocrine disorders (asthma, arthritis) require higher doses and are discussedbelow.
3. Because prolonged high-dose therapy can produce serious adverse effects, thepotential benefits of treatment must be weighed carefully against these potentiallyserious effects.
4. The glucocorticoid drugs (e.g., cortisone, prednisone), which are also known ascorticosteroids, are nearly identical to the glucose-regulation steroids producedby the adrenal cortex.
5. Glucocorticoids have two effects: (1) alteration of glucose metabolism is elicitedby low doses of steroids; (2) suppression of inflammation occurs with high dosesof steroids.
6. In high (pharmacological) doses, these agents are used to treat inflammatorydisorders (e.g., asthma, arthritis).
7. Glucocorticoids have an unfavorable impact on protein metabolism. These agentssuppress synthesis of proteins from amino acids and divert amino acids for pro-duction of glucose. These actions can cause a reduction in muscle mass, thinningof the skin, and a decrease in the protein matrix of bone. Nitrogen balance alsobecomes negative.
Drugs for Inflammatory and Allergic Disorders ◆ 91
8. The most consistent effect of glucocorticoids on fat metabolism is stimulationof lipolysis (fat breakdown). Long-term high-dose therapy can cause fat redis-tribution, resulting in the pot belly, “moon face,” and “buffalo hump” that typifyCushing’s disease.
9. Glucocorticoids are required to maintain the functional integrity of the vascularsystem. When levels of endogenous glucocorticoids are low, capillaries becomemore permeable, vasoconstriction is suppressed, and blood pressure falls, as seenin Addison’s disease.
10. Glucocorticoids increase the number of circulating red blood cells. Counts oflymphocytes, eosinophils, basophils, and monocytes are reduced.
11. Synthesis and release of glucocorticoids is regulated by a negative feedbackloop. The principal components of this loop are the hypothalamus, the anteriorpituitary, and the adrenal cortex.
12. The loop is turned on when stress or some other stimulus from the central ner-vous system (CNS) acts on the hypothalamus to cause release of corticotropin-releasing factor (CRF). CRF then stimulates the pituitary to release adrenocorti-cotropic hormone (ACTH), which in turn acts on the adrenal cortex to promotesynthesis and release of cortisol.
13. When steroids are administered chronically in large doses, the feedback loop(ACTH) remains continuously suppressed. This persistent inhibition can causeaddisonian crisis, especially if the client is stressed (e.g., due to surgery). Treat-ment for addisonian crisis is IV cortisone, often administered in the form ofSolu-Cortef.
14. Adrenal suppression is caused during long-term steroid therapy because the pi-tuitary loses much of its ability of manufacture ACTH, and in response to theprolonged absence of ACTH, the adrenal cortex becomes atrophic and loses itsability to synthesize cortisol and other glucocorticoids.
15. As a result, when prolonged therapy with steroids is discontinued, there is aperiod during which the adrenal glands are unable to produce glucocorticoids,resulting in addisonian crisis.
16. It may take from a few weeks to more than a year for the adrenal gland to recoverand produce glucocorticoids in sufficient quantities to maintain normal bodyfunction.
17. When stress is severe (e.g., surgery) these glucocorticoids are essential for sup-porting life.
18. Accordingly, it is imperative that clients receiving long-term glucocorticoid ther-apy be given increased doses at times of stress (unless the dosage is already veryhigh).
19. Furthermore, once glucocorticoid use has ceased, supplemental doses will berequired whenever stress occurs until recovery of adrenal function is complete.
92 ◆ Chapter 8
◆ Glucocorticoid Agents
Generic Name Trade Name Route
Short-acting glucocorticoids
Cortisone Cortone PO, IM
Dexamethasone Decadron Oral, topical dermatologic aerosol and
gel, ophthalmic suspension
Methylprednisolone Medrol, Depo-Medrol,Solu-Medrol
PO, IV, IM
Prednisone No commonly used
trade name
PO
Long-acting glucocorticoids
Hydrocortisone Cortef PO, IM, IV
Prednisolone Delta-Cortef PO
Triamcinolone Aristocort, Atolone PO, IM, inhalant
Nasal corticosteroids
Fluticasone, propionate Flonase Used as preventive treatment for asthma,
not as primary treatment; may take
several weeks to work; clean nasal
spray adapter weekly; adult: 2 sprays
in each nostril daily; approved for
children 4–11 years old
Flovent Rotadisk Used to treat allergic rhinitis in those
≥4 years old; 2 sprays in each nostril
daily
Flovent Diskus Used as prophylactic treatment of asthma
for patients who require a
corticosteroid in those ≥4 years old;
88–220 �g twice daily using
provided inhalation device
Fluticasone Flovent Used to reduce swelling in the lungs so
more air can move through them
Dexamethasone sodium
phosphate
Decadron Phosphate,Dalalone
Used for the control of bronchial asthma
requiring corticosteroids in
conjunction with other therapy;
intranasal: for relief of symptoms of
seasonal or perennial rhinitis that
responds poorly to other treatments
NURSING IMPLICATIONS
1. Most clients receiving long-term glucocorticoid therapy should be on a high-potassium, low-sodium diet to counter the potassium-depleting and sodium-retaining effects of the drugs.
Drugs for Inflammatory and Allergic Disorders ◆ 93
2. Clients should limit intake of alcohol, caffeine, aspirin, and other gastric irritantsto minimize peptic ulceration.
3. Long-term therapy may require increased protein intake to decrease the effectsof protein catabolism.
4. Glucocorticoids with high mineralocorticoid potency (cortisone, hydrocortisone)can cause significant retention of sodium and water, coupled with depletion ofpotassium.
5. These mineralocorticoid effects can be especially hazardous for clients withhypertension or congestive heart failure and for clients taking digitalis glycosides.
6. A negative nitrogen balance can result from glucocorticoid-induced breakdownof protein. The patient should be advised to consume a high-protein diet, andshould be provided with a diet plan or a list of appropriate foods.
7. Cataracts are a common complication of long-term glucocorticoid therapy. Tofacilitate early detection, the patient should be encouraged to have an ophthalmo-logic examination every 6–8 months. Advise the patient to contact the physicianif vision becomes cloudy or blurred.
8. Assess and educate the patient regarding increased susceptibility to infection bysuppression of the immune system.
9. Long-term glucocorticoid therapy can induce Cushing’s syndrome, whose symp-toms are identical to those of naturally occurring Cushing’s disease. Symptomsare hyperglycemia, glycosuria, fluid and electrolyte disturbances, osteoporosis,muscle weakness, cutaneous striations, and lowered resistance to infection. Re-distribution of fat produces a large abdomen, “moon face,” and “buffalo hump.”Remember that these signs and symptoms indicate the exact opposite of adrenalinsufficiency (Addison’s disease).
10. Observe for signs and symptoms of peptic ulcer disease.
11. Educate clients regarding fluid and electrolyte disturbances (sodium and waterretention) and obtain client weight before therapy begins. Also, establish a base-line for hematological values, serum electrolytes, serum glucose, and potassiumloss.
12. Osteoporosis is a frequent and serious complication of chronic glucocorticoidtherapy. Osteoporosis results from steroids inhibiting the activity of osteoblasts(cells responsible for formation of bone).
13. Educate clients regarding signs and symptoms of hyperglycemia, a side effect ofglucocorticoid therapy.
14. Observe and educate clients regarding signs and symptoms of myopathy mani-fested by muscle weakness.
15. Watch for growth retardation; glucocorticoids can suppress growth in children.
16. Assess and educate clients regarding signs of psychological disturbances (de-pression, euphoria, mania, and other psychological problems).
17. The intensity of these effects increases with dosage and duration of treatment.
94 ◆ Chapter 8
18. These toxicities are not seen when dosage is low and treatment is brief (a fewdays or a week).
19. Withdrawal of glucocorticoids is done slowly. The withdrawal schedule is deter-mined by the degree of adrenal suppression.
a. Adrenal insufficiency: monitor for sodium and water loss, hyperkalemia, hy-poglycemia, and infection (caused by depressed immune response).
b. Instruct the client to report withdrawal symptoms, including weakness,lethargy, malaise, restlessness, psychological despondency, anorexia, andnausea.
DRUG THERAPY FOR RHEUMATOID ARTHRITIS
Rheumatoid arthritis is the most common systemic inflammatory disease, affecting be-tween 6 and 9 million Americans. Although the disease can develop at any age, initialsymptoms usually appear in the third or fourth decade of life.
DRUG THERAPY FOR ARTHRITIS INCLUDESTHREE MAJOR CATEGORIES
Drug therapy for arthritis is based on severity of symptoms, the client’s response totreatment, and the client’s ability to tolerate a drug’s side effects.
1. Nonsteroidal anti-inflammatory drugs (NSAIDs) can be subdivided into salicylates(e.g., aspirin) and nonsalicylates (e.g., ibuprofen). They provide rapid relief ofsymptoms but do not alter disease progression. NSAIDs are presented earlier inthis chapter.
2. Glucocorticoid agents are also used, and are also presented earlier in this chapter.
3. Disease-modifying antirheumatic drugs (DMARDs) can be subdivided into:(1) first-choice DMARDs (e.g., hydroxychloroquine, gold salts), and (2) otherDMARDs (e.g., methotrexate, cyclophosphamide). These drugs often retard theprogression of rheumatoid arthritis. However, the onset of therapeutic effects is de-layed, typically for 2–5 months. (Note that DMARDs are more toxic than NSAIDs,and therefore treatment requires rigorous monitoring.)
DISEASE-MODIFYING ANTIRHEUMATIC DRUGS (DMARDS)
Gold Salts
1. The beneficial effect of gold salts in treating rheumatoid arthritis has been knownsince the 1930s.
2. Gold can relieve pain and stiffness, and for some clients may arrest the progressionof joint degeneration.
3. The therapeutic effect of gold takes 4–6 months to develop.
Drugs for Inflammatory and Allergic Disorders ◆ 95
4. Gold preparations are available for IM and oral use. Clients receiving IM therapyrequire repeated injections over a prolonged period.
5. The oral preparation is more convenient and less toxic than IM gold salts. Unfor-tunately, the oral preparation is also less effective.
Nursing Implications
1. Among the most common reactions are intense pruritus, rashes, and stomatitis(lesions of the oral cavity).
2. Renal toxicity, manifested as proteinuria (cloudy urine), thrombocytopenia, aplas-tic anemia, agranulocytosis (acute low white cell count), and leukopenia (abnormaldecrease in white blood cells) are rare.
3. Other serious toxicities include encephalitis, hepatitis, severe hypotension, andperipheral neuritis.
4. Frequent laboratory tests and clinical evaluations are required.
5. A baseline assessment should include the extent of joint involvement, discomfort,and mobility, hepatic and renal function values, WBC count, platelet count, andurinalysis.
Hydroxychloroquine (Plaquenil)
Hydroxychloroquine (Plaquenil), a drug with antimalarial action, can produce remissionin patients with rheumatoid arthritis. The drug may be prescribed early in the course ofthe disease in an effort to delay joint degeneration.
Nursing Implications
1. Like gold salts, hydroxychloroquine has a delayed onset of action; full therapeuticeffects take 3–6 months to develop.
2. Concurrent therapy with anti-inflammatory agents (NSAIDs or steroids) is indi-cated during the latency period.
3. The mechanism by which gold therapy or hydroxychloroquine acts is unknown.
4. The most serious toxicity is retinal damage. Retinopathy may be irreversible andcan produce blindness.
Cytoxan, Methotrexate, and Imuran
1. The anticancer drugs Cytoxan (cyclophosphamide), methotrexate, and Imuran(azathioprine) can relieve symptoms of severe arthritis. In some cases, prolongedremission may be induced. Two of these drugs, cyclophosphamide and azathio-prine, are considered very toxic, and are generally reserved for patients who havenot responded to safer medications. Methotrexate (no commonly used trade name)is the fastest acting of the disease-modifying antirheumatic drugs; therapeutic ef-fects may be seen as early as after 3–6 weeks.
2. Many physicians consider methotrexate the first-line drug among the DMARDs.
96 ◆ Chapter 8
3. Major toxicities are hepatic fibrosis, bone marrow depression, gastrointestinalulceration, and pneumonitis.
Note: Methotrexate is also used to treat ectopic pregnancies and can be usedfor medical abortions. The drug works by blocking cell growth. Unlike a sur-gical abortion, in which the fetal embryo is scraped or suctioned from theuterus, a woman simply takes the drug and the embryo is aborted, much like amiscarriage.
Nursing Implications
1. Periodic tests of liver and kidney function are mandatory, as are complete bloodcounts and platelet counts for all clients on anticancer drugs.
2. Assess clients for infections, as anticancer drugs depress the bone marrow.
3. Methotrexate can cause fetal death and congenital abnormalities; therefore, thedrug is contraindicated during pregnancy.
4. Methotrexate may be administered once weekly, beginning at 5 mg. The dose maybe gradually increased to a maximum of 15–20 mg.
5. Azathioprine (Imuran): the antiarthritic effects of this drug are equivalent to thoseof gold salts and hydroxychloroquine. This drug is classified as an immunosup-pressant. Benefits are derived from immunosuppressive and anti-inflammatoryactions. Imuran is also employed to prevent organ rejection.
6. Serious toxicities of Imuran include hepatitis and blood disorders (leukopenia,thrombocytopenia, anemia). Because of these severe side effects, the drug is re-served for patients with life-threatening complications.
7. Cytoxan as a treatment for rheumatoid arthritis is still under investigation. Thedrug is considered more toxic than methotrexate or Imuran. Serious toxicitiesinclude marrow depression, sterility, hemorrhagic cystitis, and mucous membranelesions.
DRUG THERAPY FOR GOUT
1. Gout is a recurrent inflammatory disorder characterized by hyperuricemia (highblood levels of uric acid) and episodes of severe joint pain, typically in the largetoe.
2. Foods high in purines, which aggravate gout, include kidney, liver, poultry, fish,sweetbreads (the thymus gland of an animal such as a cow), anchovies, sardines,and gravies.
3. Six principal drugs are employed to treat gout. Two of these agents, colchicineand indomethacin (Indocin), relieve inflammation.
4. The other four agents are allopurinol (Zyloprim), phenylbutazone (Butazolidin),probenecid (Benemid), and sulfinpyrazone (Anturane). These are used to decreaseuric acid.
Drugs for Inflammatory and Allergic Disorders ◆ 97
5. Allopurinol is generally well tolerated. The most serious toxicity is a rare, butpotentially fatal, hypersensitivity syndrome, characterized by rash, fever, and dys-function of the liver and kidneys.
6. Like other NSAIDs, indomethacin, colchicine, allopurinol, probenecid, andphenylbutazone may cause gastrointestinal reactions (nausea, vomiting, diarrhea,abdominal discomfort).
◆ Agents Used to Treat Gout and Gouty Arthritis
Generic Name Trade Name
Allopurinol ZyloprimDesired effect: Decrease uric acid
Side effects: Rash, renal failure, bone marrow depression, hepatitis,
GI disturbance
Probenecid BenemidSide effects: Headache, nausea, vomiting, urinary frequency,
aplastic anemia, GI disturbance
Phenylbutazone ButazolidinSide effects: Headache, dizziness, edema, hearing loss, aplastic anemia, GI
disturbance
Sulfinpyrazone AnturaneSide effects: Rash, kidney stones, nausea, vomiting, blood dyscrasias, GI disturbance
Colchicine No commonly used trade name
Indomethacin IndocinDesired effect: Relieve inflammation
Side effects: Gastric ulceration, bone marrow depression, aplastic anemia,
mental confusion, peripheral neuritis
Chapter
9 Respiratory Tract Drugs
DRUG THERAPY FOR ASTHMA
1. Asthma is a very common disorder that affects both children and adults. In theUnited States, asthma affects between 10 and 20 million people.
2. Unfortunately, there is no cure for asthma; drugs can only provide symptomaticrelief.
3. Beta-2 adrenergic agonists (e.g., terbutaline [Brethine], albuterol [Ventolin]) are amainstay of antiasthmatic therapy. These drugs are taken by practically all clientswho experience asthma attacks.
4. For treatment of asthma, beta-2 agonists are usually administered by inhalation.However, preparations for oral and parenteral use are also available.
5. Adrenergic agonists are discussed in Chapter 2. In this chapter, discussion ofadrenergic agonists is limited to their use in treating asthma.
6. Drugs used to treat respiratory infections are presented in Chapter 12.
98
Respiratory Tract Drugs ◆ 99
◆ Beta-2 Adrenergic Agonists (Synthetic Catecholamines)
Generic Name Trade Name
Albuterol Proventil, VentolinEpinephrine (adrenaline) AsthmaNefrin
Isoetharine BronkosolTheophylline Theo-DurMetaproterenol AlupentTerbutaline BrethineSalmeterol xinafoate Serevent DiskusFormoterol fumarate Foradil AerolizerPirbuterol acetate Maxair AutohalerTreatment: Beta-2
Adrenergic Agonists
Asthma, chronic obstructive pulmonary disease (COPD)
Desired effects: • Proventil, Ventolin: bronchodilator, vasodilator
Side effects: Restlessness, apprehension, anxiety, fear, insomnia, tremors, irritability,
cardiac arrhythmias, sweating
Desired effects: • Epinephrine: bronchodilator, antiasthmatic, cardiac stimulant, mydriatic,
nasal decongestant, vasopressor
Side effects: Restlessness, apprehension, anxiety, fear, insomnia, tremors, irritability,
cardiac arrhythmias, sweating, tachycardia
Desired effects: • Bronkosol: bronchodilator
Side effects: Irritability (especially in children) restlessness, dizziness, severe
depression, life-threatening arrhythmias, loss of appetite
Desired effects: • Theophylline
Sympathetic relief or prevention of bronchial asthma and reversible
bronchial spasms associated with chronic bronchitis and emphysema
Side effects: Irritability (especially in children), restlessness, life-threatening ventricle
arrhythmias, respiratory arrest, proteinuria, loss of appetite
Desired effects: • Alupent: bronchodilator
Side effects: Restlessness, apprehension, anxiety, fear bronchospasm
Desired effects: • Brethine: bronchodilator
Side effects: Restlessness, apprehension, anxiety, fear, cardiac arrhythmias,
palpitations, respiratory difficulties
Desired effects: • Serevent Diskus: bronchodilator; also inhibits the release of
inflammatory mediators in the lung, blocking swelling and inflammation
Side effects: Headache, tremor, tachycardia, palpitations, hypertension,
bronchospasm
Desired effects: • Foradil Aerolizer: bronchodilator; also inhibits the release of
inflammatory mediators in the lung, blocking swelling and inflammation
(continued)
100 ◆ Chapter 9
◆ Beta-2 Adrenergic Agonists (SyntheticCatecholamines) (continued)
Generic Name Trade Name
Side effects: Tremor, dizziness, insomnia, headache, nervousness, hypertension,
tachycardia, chest pain, bronchitis, viral infections (most likely in
children)
Desired effects: • Maxair Autohaler: bronchodilator (and vasodilator); at high doses
beta-2 selectivity is lost and the drug also acts on beta-1 receptors
to cause typical sympathomimetic cardiac effects
◆ Antiasthmatic Glucocorticoids
Generic Name Trade Name (Route)
Prednisone Deltasone (PO)
Budesonide Rhinocort (inhalation)
Mometasone furoate Nasonex (inhalation)
Dexamethasone sodium
phosphate
Decadron Phosphate (inhalation, IM, IV)
Budesonide Pulmicort, Rhinocort Aqua (inhalation)
Beclomethasone Vanceril, Vanceril Double Strength (inhalation)
Triamcinolone acetonide Azmacort (inhalation, IM)
Desired effect: Control of bronchial asthma; corticosteroids are used in conjunction
with other therapy; prophylactic therapy may also be used.
Side effects: Adverse effects depend on dose, route, and duration of therapy;
inhalational adverse effects include nasal irritation, fungal
infections, epistaxis, rebound congestion, and perforation of
nasal septum
Note: Doctors usually recommended inhaled corticosteroids instead of oral steroids because the mist goes directly into the
lungs, and less of the medication reaches other parts of the body, keeping side effects to a minimum. Most patients need to
use the inhaler several times a day, and the proper dose is the smallest one that keeps the patient free of attacks. Heavy use of
these inhalers may slow growth in children, perhaps by a third of an inch a year.
TEACHING POINTS FOR CLIENTS
Rinse your mouth after inhalant therapy. Use the product exactly as prescribed, and donot stop taking the drug without consulting your health care provider. The drug shouldnot be stopped abruptly but must be slowly tapered.
Respiratory Tract Drugs ◆ 101
Teaching Patients How to Use Devices thatHelp Monitor and Control Asthma
1. Peak flow meter: Teach the patient to blow hard and quickly into the instrument,which slides a gauge to within one of three zones: green for health, yellow forcaution, and red for medical alert.
2. Metered-dose inhaler: Teach the patient to breathe in, press the canister down intothe mouthpiece, and continue to inhale the medication as it is released. Inhalersdeliver metered doses of medicine to the lungs.
3. Spacer: Teach the patient to spray medication into the plastic bag instead of directlyinto the mouth, and the medication is inhaled via a mouthpiece without depositingmedicine directly in the mouth and throat. The spacer works by allowing the patientto inhale medication more slowly.
◆ Other Antiasthmatic and Antiallergenic Agents
Generic Name Trade Name
Nedocromil sodium Tilade (inhalation)
Cromolyn sodium Intal (inhalation)
Desired effects: Decreases the release of histamine and blocks the overall inflammatory
reaction
Side effects: Cough, nasal congestion, headache, fatigue, bad taste
Note: Intal and Tilade are not as powerful as the inhaled corticosteroids.
Leukotriene formation inhibitorsZileuton Zyflo (PO)
Montelukast sodium Singulair (PO)
Zafirlukast Accolate (PO)
Desired effects: Decrease inflammation, edema, mucus secretion, and bronchoconstriction
associated with asthma; this is accomplished by selectively and
competitively blocking the receptor that causes leukotriene formation,
thus blocking many of the signs and symptoms of asthma, including
neutrophil and eosinophil migration, neutrophil and monocyte
aggregation, leukocyte adhesion, increased capillary permeability, and
smooth muscle contraction
Treatment: Asthma, COPD
Side effects: Alopecia, edema, Cushing’s syndrome, epistaxis, nasal irritation, fungal
infection, paresthesias, nervousness, weight gain, hyperglycemia
Note: Liver enzyme elevation is an adverse side effect of Zyflo and Accolate.
(continued)
102 ◆ Chapter 9
◆ Other Antiasthmatic and Antiallergenic Agents (continued)
Generic Name Trade Name
AntihistaminesLoratadine ClaritinFexofenadine AllegraBrompheniramine maleate No trade nameChlorpheniramine maleate Chlor-TrimetonCetirizine ZyrtecDiphenhydramine BenadrylDimenhydrinate DimetabsHydroxyzine VistarilDesired effect: • Claritin: competitively blocks the effects of histamine at H1-receptor
sites; has anticholinergic (atropinelike), antipruritic, and sedative effects
Treatment: Symptomatic relief of perennial and seasonal allergic rhinitis, vasomotor
rhinitis, allergic conjunctivitis, and mild uncomplicated urticaria and
angioedema
Side effects: Drowsiness, headache, nervousness, dizziness, depression, drowsiness,
palpitations, increased appetite, fever, weight gain
Desired effects: Allegra, Chlor-Trimeton, Benadryl: competitively block the effects of
histamine at H1-receptor sites; anticholinergic (atropinelike),
antipruritic, and sedative effects
Side effects: Drowsiness, sedation, dizziness, disturbed coordination, fatigue,
anaphylactic shock, hemolytic anemia, thickening of bronchial
secretions
Desired effects: • Zyrtec: potent histamine H1-receptor antagonist; inhibits histamine
release and eosinophil chemotaxis during inflammation, leading to
reduced swelling and decreased inflammatory response
Side effects: Somnolence, sedation, bronchospasm, palpitation
Desired effects: • Dimetabs: antihistamine with antiemetic and anticholinergic activity;
depresses hyperstimulated labyrinthine function; may block synapses in
the vomiting center; peripheral anticholinergic effects may contribute to
anti–motion sickness efficacy
Side effects: Drowsiness, confusion, nervousness, restlessness, headache, dizziness,
vertigo, insomnia, weakness of hands, seizures
Desired effects: • Atarax, Vistaril: mechanism of action not understood; action may be
due to suppression of subcortical areas of the CNS; has clinically
demonstrated antihistaminic, analgesic, and bronchodilator activity
Side effects: Drowsiness, involuntary motor activity including seizures, dry mouth,
urinary retention, wheezing, dyspnea
Respiratory Tract Drugs ◆ 103
METHYLXANTHINES
Caffeine
1. Caffeine is the most familiar member of this family.
2. Caffeine is present in tea, coffee, cola drinks, and cocoa.
3. In low doses, caffeine decreases drowsiness and fatigue and increases the capacityfor prolonged intellectual exertion. With increasing dosage, caffeine producesnervousness, insomnia, and tremors.
4. High doses of caffeine stimulate the heart. When caffeine-containing beveragesare consumed in excessive quantities, arrhythmias may result.
5. In the peripheral blood vessels caffeine promotes vasodilation, and in the CNS itis an effective stimulant.
6. Caffeine and other methylxanthines promote bronchodilation.
7. Caffeine is a diuretic. The mechanism by which it increases urine formation is notfully understood.
8. Caffeine is used primarily as an aid to stay awake.
Theophylline
1. Theophylline (Bronkodyl, others) is the principal methylxanthine employed totreat asthma. Benefits derive primarily from bronchodilation.
2. Theophylline has a narrow therapeutic range, and dosage must be carefullycontrolled.
3. The drug is usually administered by mouth.
4. Side effects include nervousness, anxiety, and tachycardia.
Aminophylline
1. Aminophylline (Truphylline) is a theophylline salt that is considered more solublethan theophylline itself.
2. Because of its relatively high solubility, aminophylline is the preferred form oftheophylline for intravenous use.
Cromolyn Sodium
1. Cromolyn sodium (Intal) is a very safe and effective drug for prophylaxis ofasthma, but is not useful for aborting an ongoing asthma attack. Administration isby inhalation.
2. Cromolyn is used for prophylactic therapy of mild to moderate chronic asthma.
3. The drug produces adequate control in 60–70% of clients.
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4. When administered on a regular schedule, cromolyn reduces both the intensityand frequency of attacks.
5. Adverse effects: cromolyn sodium is the safest of all antiasthmatic medications.The most common reactions are wheezing and coughing in response to inhalationof powdered cromolyn.
Glucocorticoids
1. Glucocorticoids (e.g., prednisone) are the most effective antiasthmatic drugs avail-able. The drugs can be administered orally, intravenously, or by inhalation.
2. Glucocorticoids reduce symptoms of asthma primarily by suppressing inflamma-tion.
3. As a result of suppressing inflammation, glucocorticoids reduce bronchial hyper-activity. In addition to reducing inflammation, glucocorticoids decrease airwaymucus production and increase the number of bronchial beta-2 adrenergic recep-tors, as well as their responsiveness to beta-2 agonists.
4. Glucocorticoids are used for prophylaxis in clients with chronic asthma.
5. Inhalational glucocorticoids are now considered a first-line therapy for asthma.
6. Oral glucocorticoids are reserved for clients with severe asthma. Because of theirpotential for toxicity, these drugs are prescribed only when symptoms cannotbe controlled with safer medications (e.g., beta-2 agonists, theophylline, amino-phylline). Because the risk of toxicity increases with duration of use, treatmentshould be as short as possible.
7. Possible adverse effects from prolonged use of oral glucocorticoids include osteo-porosis, hyperglycemia, peptic ulcer disease, and in young clients, suppression ofgrowth.
8. Adrenal suppression is of particular concern, as discussed in Chapter 8.
Chapter
10Gastrointestinal Drugs
DRUGS FOR PEPTIC ULCER DISEASE
1. Despite commonly held beliefs, dietary factors play only a minor role in ulcer man-agement. The traditional “ulcer diet” consisting of bland foods does not increasehealing. There is also no convincing evidence that caffeine-containing beveragespromote ulcer formation or interfere with recovery.
2. Smoking is associated with an increased incidence of ulcers; it also retards recov-ery. Accordingly, cigarettes should be avoided.
3. Because of their ulcerogenic actions, aspirin and other NSAIDs should be avoided.
4. Stress and anxiety may aggravate an existing ulcer.
5. Antiulcer drugs fall into five major classes: (1) antisecretory agents (e.g., Tagamet),(2) agents that enhance mucosal protection (e.g., Carafate), (3) antisecretory agentsthat enhance mucosal defense (e.g., Cytotec), (4) antacids (e.g., Amphojel), and(5) antibiotics (e.g., Flagyl).
105
106 ◆ Chapter 10
◆ Antiulcer Agents
Generic Name Trade Name
Antisecretory agents: Histamine2 (H2)-antagonists
Cimetidine TagametFamotidine PepcidNizatidine AxidRanitidine ZantacDesired effects: Inhibits the action of histamine at the H2 receptors of the stomach and reduces
total pepsin output; Tagamet is available over-the-counter at one-half the
prescription strength.
Major side effects: Cardiac arrest, impotence (reversible), dizziness, peripheral neuropathy,
hallucinations, confusion
Nursing implications: Take with meals and at bedtime; therapy may be continued for 4–6 weeks or
longer; teach patients to have regular follow-up care to evaluate their
response; educate patients about side effects and tell them to report side
effects to the health caregiver.
Antisecretory agents: Proton pump inhibitors
Omeprazole PrilosecLansoprazole PrevacidEsomeprazole
magnesium
Nexium
Rabeprazole AciphexDesired effects: Suppress gastric acid secretion by specific inhibition of the
hydrogen-potassium-ATPase enzyme system at the secretory surface of the
gastric parietal cells, blocking the final step of acid production
Major side effects: Dizziness, somnolence, headache, confusion, diarrhea, sexual impotence
(reversible), somnolence, insomnia, diarrhea, constipation
Nursing implications: Tell the patient to take the drug 1 hour before meals; swallow the capsules
whole; do not chew or crush; if the patient cannot swallow the capsule, it
can be opened and the contents sprinkled in applesauce or mixed in tap
water, orange juice, or yogurt; these drugs need to be taken for 4–8 weeks.
Note: All antisecretory agents are used for the treatment of active duodenal ulcers, short-term treatment of benign gastric
ulcers, to treat pathologic hypersecretory conditions (e.g., Zollinger-Ellison syndrome), erosive GERD, and for relief of
heartburn and acid indigestion. They are also used for short-term treatment (4–8 weeks) for erosive esophagitis (diagnosed
by endoscopy) and symptomatic gastroesophageal reflux disease.
Antisecretory agent that enhances mucosal defenses
Misoprostol CytotecDesired effects: A synthetic prostaglandin E1 analogue, this mucosal defense agent: (1)
suppresses secretion of gastric acid, (2) promotes secretion of bicarbonate
and cytoprotective mucus, and (3) maintains submucosal blood flow
(by promoting vasodilation), thus protecting the lining of the stomach.
(continued)
Gastrointestinal Drugs ◆ 107
◆ Antiulcer Agents (continued)
Generic Name Trade Name
Major side effects: Nausea, diarrhea, abdominal pain, flatulence, dyspepsia, constipation,
miscarriage, excessive bleeding, spotting, cramping, hypermenorrhea,
menstrual disorders, dysmenorrhea
Treatment: Prevention of NSAID-induced gastric ulcers, including those caused by aspirin
Nursing implications: Give to patients at high risk for developing NSAID-induced ulcers; give for the
full period of NSAID use; arrange for serum pregnancy tests for any women
of childbearing age; they must have a negative test within 2 weeks of
beginning therapy
Mucosal protectantsSucralfate CarafateBismuth Pepto-BismolDesired effects: Forms an ulcer-adherent complex at duodenal ulcer sites, protecting the ulcer
from acid, pepsin, and bile salts, thereby promoting ulcer healing; also
inhibits pepsin activity in gastric juices
Major side effects: Carafate: dizziness, vertigo, rash, pruritus, constipation, diarrhea, dry mouth,
gastric discomfort; Pepto-Bismol: darkening of stools, and fecal impaction in
infants and debilitated patients, salicylate toxicity, ringing in the ears, rapid
respirations
Treatment: Pepto-Bismol: indigestion, nausea, vomiting, and control of traveler’s diarrhea
within 24 hours; relief of gas pain and abdominal cramps; Carafate:
short-term treatment of duodenal ulcers, up to 8 weeks; maintenance
therapy for duodenal ulcer at reduced dosage after healing; treatment of oral
and esophageal ulcers due to radiation, chemotherapy, and
sclerotherapy
Nursing implications: Carafate: teach patients to take the drug on an empty stomach, 1 hour before or
2 hours after meals and at bedtime; administer antacids between doses of
Carafate, not within 30 minutes before or after Carafate; Pepto-Bismol:
instruct patients to shake liquid well before administration, have patient
chew tablets thoroughly or allow to dissolve in the mouth; do not swallow
whole; discontinue drug if any sign of salicylate toxicity (e.g., ringing in the
ears) occurs
AntacidsAluminum hydroxide Amphojel, others
Magnesium hydroxide Maalox, others
Magaldrate Riopan, others
Calcium carbonate Tums, others
Desired effects: Neutralizes or reduces gastric acidity, resulting in an increase in the pH of the
stomach and duodenal bulb and inhibition of the proteolytic activity of
pepsin, which protects the lining of the stomach
(continued)
108 ◆ Chapter 10
◆ Antiulcer Agents (continued)
Generic Name Trade Name
Major side effects: Antacids figure in numerous drug interactions owing to their action on gastric
pH (increased) and their propensity to bind with other drugs to form poorly
absorbed complexes; decreases pharmacologic effects of corticosteroids,
diflunisal, digoxin, iron, isoniazid, penicillamine, phenothiazine, ranitidine,
and tetracycline; increases effect of benzodiazepines; major side effects
include a change in bowel habits (diarrhea or constipation), nausea,
vomiting, alkalosis, and hypermagnesemia.
Treatment: Symptomatic relief of upset stomach associated with hyperacidity; hyperacidity
associated with peptic ulcers, gastritis, peptic esophagitis, hiatal hernia
Nursing implications: Give hourly for the first 2 weeks when used for acute peptic ulcer; during the
healing stage, give 1–3 hours after meals; do not administer oral drugs within
1–2 hours of antacid administration
AntibioticsMetronidazole Flagyl, others
Tetracycline Cyclopar, others
Amoxicillin Augmentin, others
Clarithromycin BiaxinDesired effects: Inhibits protein synthesis in susceptible bacteria, causing cell death
Major side effects: Flagyl: major side effects include headache, dizziness, ataxia, darkened urine,
and peripheral neuropathy; Cyclopar: major side effects include
discoloration and inadequate calcification of primary teeth of fetuses if used
by pregnant women, thrombocytopenia, leukopenia, hemolytic anemia,
nausea, and vomiting; Augmentin: major side effects include stomatitis,
gastritis, nausea, vomiting, and diarrhea; Biaxin: major side effects include
hepatotoxicity, stomatitis, anorexia, nausea, and vomiting
Note: There is a strong association between Helicobacter pylori infections and peptic ulcer disease. H. pylori is present in
95% of clients with duodenal ulcers and 75% of clients with gastric ulcers. Furthermore, eradication of the bacteria promotes
ulcer healing and minimizes recurrences. Although the mechanism by which H. pylori promotes ulcers has not been firmly
established, research has shown a definite association. The regimen for H. pylori is two or more antibiotics given concurrently,
combined with a proton pump inhibitor or an H2-receptor antagonist for 7–14 days.
LAXATIVES
1. The term laxative effect refers to production of a soft, formed stool over a periodof 1 or more days.
2. The term catharsis applies when evacuation of the bowel is liquid and prompt.
3. A laxative effect is relatively mild, whereas catharsis is more intense.
4. The principal function of the colon is to absorb water and electrolytes.
5. Proper function of the bowel is highly dependent on dietary fiber intake.
Gastrointestinal Drugs ◆ 109
6. The best source of fiber is bran. Fiber can also be obtained from fruits andvegetables.
7. Laxatives can be very beneficial when used for valid reasons.
8. By softening the stool, laxatives can reduce the painful elimination that can beassociated with hemorrhoids and other anorectal lesions.
9. In clients with cardiovascular diseases (e.g., myocardial infarction, aneurysm),softening of the stool decreases the strain needed to defecate, thereby avoidingdanger of Valsalva’s maneuver, which causes increased intrathoracic pressureand slowing of the pulse, increasing the return of blood to the heart and venouspressure.
10. In geriatric clients, high-fiber diets and exercise should be encouraged as a meansof maintaining normal bowel movements.
11. When laxatives are employed habitually, the colon becomes dependent on thelaxatives and defecation will not occur without their use.
12. Constipation is treated by establishing good health habits: consuming regularmeals with ample fiber and a consistent time for elimination, along with relax-ation, exercise, and adequate fluid intake (at least 1000 mL/day).
13. Water needs are greater in clients with decreased renal concentrating ability (suchas the elderly) since relatively more water is required to eliminate waste.
CLASSIFICATION OF LAXATIVES
1. Bulk-forming agents (e.g., Metamucil) have actions and effects very similar tothose of dietary fiber.
a. Bulk-forming laxatives are preferred agents for temporary treatment of consti-pation.
b. Bulk-forming laxatives are widely used by clients with diverticulosis and irri-table bowel syndrome.
c. In addition, by altering fecal consistency, these agents can provide symptomaticrelief of diarrhea and can reduce discomfort and inconvenience for clients withan ileostomy or colostomy.
d. Adverse effects: Since the bulk-forming agents are not absorbed, systemicreactions are rare. Esophageal or intestinal obstruction can occur if theseagents are swallowed in the absence of sufficient water. To avoid this effect,bulk-forming laxatives should be administered with a full glass of water orjuice.
e. Excessive intake of dietary fiber over several months can cause serious damageto the colon.
2. Surfactants (e.g., Colace) produce a soft stool several days after the onset oftreatment. Administration of all surfactants should be accompanied by a full glassof water.
110 ◆ Chapter 10
3. Contact laxatives (e.g., Dulcolax, castor oil) are widely used and abused by thegeneral public. The contact laxatives act on the intestinal wall to produce a netincrease in the amount of fluid and electrolytes within the intestinal lumen.
4. Saline laxatives (e.g., milk of magnesia, magnesium hydroxide) are poorlyabsorbed salts whose osmotic action draws water into the intestinal lumen. Ac-cumulation of fluid causes the fecal mass to soften and swell; swelling, in turn,stretches the intestinal wall and thereby stimulates peristalsis.
MISCELLANEOUS GASTROINTESTINAL DRUGS
ANTIEMETICS
1. Emesis (vomiting) is a complex reflex brought about by activation of the vomitingcenter, a nucleus of neurons located in the medulla oblongata.
2. Certain stimuli (e.g., gastrointestinal irritation) activate the vomiting centerdirectly.
3. A major application of the antiemetics is to suppress nausea and vomiting asso-ciated with cancer chemotherapy. For clients undergoing cancer chemotherapy,antiemetic therapy offers three major benefits: (1) reducing anticipatory nauseaand vomiting, (2) preventing the malnutrition and dehydration that can be causedby frequent nausea and vomiting, and (3) reducing discomfort, thereby increasingcompliance with the cancer chemotherapeutic program.
◆ Antiemetics
Generic Name Trade Name
Phenothiazines
Chlorpromazine ThorazineFluphenazine ProlixinProchlorperazine CompazineThiethylperazine TorecanButyrophenones
Haloperidol HaldolAntihistamines
Dimenhydrinate DramamineDiphenhydramine BenadrylHydroxyzine Vistaril, AtaraxMeclizine AntivertPromethazine Phenergan
Gastrointestinal Drugs ◆ 111
◆ Antiemetics (continued)
Generic Name Trade Name
• Others
Metoclopramide ReglanScopolamine No commonly used trade name
Trimethobenzamide TiganLorazepam AtivanDiazepam Valium
• Glucocorticoids
Dexamethasone DecadronMethylprednisolone Solu-MedrolOndansetron ZofranTreatment: • A phenothiazine (e.g., Thorazine) suppresses emesis by blocking dopamine
receptors in the medulla oblongata, a trigger zone for monitoring; it is useful
for postoperative nausea and vomiting, and for emesis caused by
chemotherapy, radiation therapy, and toxins.
• Butyrophenones (e.g., Haldol) suppress emesis by acting as a strong
anticholinergic blocking agent; it blocks dopamine receptors in the
chemoreceptor trigger zone (CTZ); the CTZ is the activating center for
vomiting located in the medulla oblongata.
• Antihistamines (e.g., Dramamine) are used to treat motion sickness; the
mechanism by which these drugs suppress emesis associated with motion
sickness is unclear.
• Metoclopramide (e.g., Reglan) has two beneficial actions: (1) it blocks
dopamine receptors in the CTZ, thereby suppressing emesis, and (2) it
increases upper GI motility by enhancing the action of acetylcholine; Reglan is
a drug of choice for suppressing nausea and vomiting caused by highly emetic
anticancer agents (e.g., cisplatin, dacarbazine); in addition, Reglan is given to
suppress postoperative emesis and emesis caused by radiation therapy, toxins,
and opioids.
• Scopolamine, a muscarinic antagonist, is the most effective drug for
prophylaxis and treatment of emesis associated with motion sickness.
• Tigan acts to suppress emesis by blocking the CTZ.
• Benzodiazepines (e.g., Valium, Ativan) are used to alleviate nausea and
vomiting associated with cancer chemotherapy; the antiemetic effect of
diazepam derives primarily from suppression of anxiety; Ativan is beneficial
because of its ability to produce antegrade amnesia.
• Glucocorticoids (e.g., Decadron, Solu-Medrol) have been employed
investigationally to treat emesis brought on by cancer chemotherapy; clinical
experience has shown these drugs to be effective alone and in combination
with other antiemetics; the mechanism by which glucocorticoids suppress
emesis is not known; both dexamethasone (Decadron) and
methylprednisolone (Solu-Medrol) are administered intravenously.
(continued)
112 ◆ Chapter 10
◆ Antiemetics (continued)
Generic Name Trade Name
Treatment:
(continued)
• Ondansetron (Zofran) is a new drug used to suppress nausea and vomiting
associated with cancer chemotherapy; this drug acts by blocking serotonin
receptors in the medulla oblongata on the vagal neurons in the upper GI tract;
Zofran has proved to be very effective.
Side effects: • Phenothiazines (e.g., Thorazine) can produce a variety of serious side effects;
these include hypotension, sedation, extrapyramidal reactions, and
anticholinergic effects.
• Butyrophenones (e.g., Haldol) have potential side effects similar to those of
the phenothiazines: extrapyramidal reactions, sedation, and hypotension.
• Metoclopramide (e.g., Reglan) side effects include extrapyramidal reactions
(especially in children), diarrhea, and sedation.
• Antihistamines (e.g., Vistaril, Atarax) side effects include drowsiness, dry
mouth, ataxia, and dizziness.
• Common side effects of scopolamine and Atarax include sedation, dizziness,
orthostatic hypotension, dry mouth, constipation, headache, and
tachycardia.
• Side effects of glucocorticoids (e.g., Decadron) include depression,
euphoria, hypertension, anorexia, decreased wound healing, ecchymoses,
adrenal suppression, and hyperglycemia.
• Side effects of benzodiazepines (e.g., Valium, Ativan) include drowsiness,
sedation, depression, lethargy, apathy, fatigue, confusion, bradycardia,
tachycardia, and drug dependence.
• Side effects of dexamethasone (Decadron) and methylprednisolone
(Solu-Medrol) include vertigo, headache, euphoria, mood swings,
depression, psychosis, immunosuppression, masking of infections, impaired
wound healing, and adrenal cortex suppression.
• Side effects of ondansetron (e.g., Zofran) are headache and diarrhea.
Notes: Antivert is also used for dizziness and motion sickness. It is used most often to treat nausea and vomiting associated
with Meniere disease.
Benzodiazepines and glucocorticoids are used before administration of cancerchemotherapy.
ANTIDIARRHEAL AGENTS
Opioids are the most effective antidiarrheal drugs. By stimulating opioid receptors in theGI tract, these agents suppress peristalsis, thereby facilitating absorption of water andelectrolytes. As a result, the fluidity and volume of stools are reduced, as is frequencyof defecation.
Gastrointestinal Drugs ◆ 113
◆ Opioids Used to Treat Diarrhea
Generic Name Trade Name
Diphenoxylate
(plus atropine)
Lomotil
Loperamide ImodiumParegoric No commonly used trade name
Desired effects: Decrease GI peristalsis
Side effects: Lomotil: drowsiness, headache, paralytic ileus, toxic megacolon, and
sedation
Imodium: toxic megacolon, respiratory depression, drowsiness
Paregoric (which is camphorated tincture of opium and contains 0.4 mg
morphine/mL): depression, dizziness, drowsiness, fainting, and
constipation
Treatment: Diarrhea
Nursing implications: Advise patients that constipation can result from overuse of these drugs;
encourage patients to drink clear liquids and not to ingest fried foods
or milk products until after diarrhea has stopped; monitor the
frequency of bowel movements and bowel sounds; educate patients
to notify health caregiver if intestinal hypoactivity occurs when taking
these drugs.
DRUGS FOR INFLAMMATORY BOWEL DISEASE
1. Inflammatory bowel disease has two principal forms: Crohn’s disease and ulcer-ative colitis.
2. Sulfasalazine (Azulfidine) is most effective in the treatment of acute episodes ofmild to moderate ulcerative colitis.
3. Azulfidine may also benefit clients with acute Crohn’s disease.
4. Adverse side effects include nausea, fever, anemia, and agranulocytosis (acute lowwhite cell count).
5. Glucocorticoids can relieve symptoms of ulcerative colitis and Crohn’s disease.Benefits derive from the anti-inflammatory action of these drugs. As discussedin Chapter 8, long-term use of glucocorticoids can cause severe adverse effects,including adrenal cortex suppression, osteoporosis, increased susceptibility to in-fection, and a Cushing’s-like effect.
6. Immunosuppressive agents are also use to treat Crohn’s disease. Drugs such asImuran, Cytoxan, and methotrexate are used to suppress inflammation. Side ef-fects include nausea, vomiting, hepatotoxicity, leukopenia, thrombocytopenia, andcarcinogenesis.
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VITAMINS
1. Vitamin B12 (cyanocobalamin) must be taken for life IM for pernicious anemia.
2. Vitamin B6 (pyridoxine) is necessary for neurological transmission.
3. Vitamin C (ascorbic acid) is necessary to prevent scurvy and assist with woundhealing.
FAT-SOLUBLE VITAMINS
Nursing Implications
1. Fat-soluble vitamins A, D, E, and K are stored in the liver in large amounts.
2. Vitamin K is needed for the production of prothrombin. Vitamin K is formedby bacteria in the gastrointestinal tract. It is given to all newborn babies becausethe neonate has a sterile bowel and bacteria are necessary for the formation ofvitamin K. It is also given before liver surgery because vitamin K is stored in theliver.
3. Vitamin D is necessary for the absorption of calcium. It is produced when the skinis exposed to sunlight. Milk is fortified with vitamin D.
◆ Fat-Soluble Vitamins
Vitamin Trade Name
Vitamin K AquaMEPHYTONVitamin D CalderolVitamin A AlphalinVitamin E Aquasol E
◆ Pancreatic Enzymes
Generic Name Trade Name
Pancrelipase Viokase, others
Pancreatin No common trade name
Treatment: Pancreatic insufficiency is associated with chronic pancreatitis, pancreatomy, and
cystic fibrosis.
Desired effect: Replacement of pancreatic enzymes in clients with pancreatic insufficiency
Side effects: Diarrhea, nausea, stomach cramps, abdominal pain (high doses only), hematuria,
rash, hives
Chapter
11Ophthalmic Drugs
DRUGS USED FOR DISORDERS OF THE EYE
1. The term glaucoma refers to a group of diseases characterized by elevations ofintraocular pressure (IOP). Increased IOP can cause damage to the optic nerveand blindness.
2. Glaucoma has two principal forms: open-angle glaucoma and closed-angleglaucoma.
3. In both forms, the cause of abnormally high IOP is impairment of aqueous humoroutflow from the anterior chamber of the eye.
4. Open-angle glaucoma is by far the most common cause of increased IOP.
5. Approximately 90–95% of individuals with glaucoma have the open-angle formof the disease.
6. Open-angle glaucoma is a painless, insidious disease in which injury to the eyedevelops over a period of years. Symptoms are usually absent until extensivevisual damage has been produced.
7. Open-angle glaucoma is usually bilateral and may progress insidiously to com-plete blindness without ever producing an acute attack.
8. There may be times when a person with chronic open-angle glaucoma noticesa loss of peripheral vision or has foggy vision and diminished accommodation.Peripheral vision is gradually lost over a period of years and may be the first andonly symptom the client experiences.
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116 ◆ Chapter 11
9. The disease usually has a genetic basis and is most common in those over theage of 40.
10. Open-angle glaucoma is managed primarily by chronic drug therapy.
11. Drugs decrease IOP by either (1) promoting outflow of aqueous humor, or(2) decreasing aqueous humor production.
12. Acute angle-closure glaucoma is a medical emergency. The aim of treatment isto open the closed chamber angle and permit outflow of aqueous humor. Whilethis goal may sometimes be achieved medically, surgery is usually eventuallyrequired.
13. Acute angle-closure glaucoma may produce symptoms in which the person ex-periences transitory attacks characterized by diminished visual acuity, coloredhalos around lights, and head and eye pain. These transitory attacks may last onlya few hours, recurring at intervals of weeks or years before the person experiencesfull-blown prolonged attacks of acute glaucoma.
14. Urgent reduction of IOP is best accomplished by the use of hyperosmotic agents,including oral glycerin and sorbitol or IV mannitol. Laser surgery or surgicaliridotomy is curative in most cases.
◆ Ophthalmic Agents to Decrease Production ofAqueous Humor
Generic Name Trade Name
Acetazolamide (carbonic
anhydrase inhibitor)
Diamox
Levobunolol (beta blocker) BetaganTimolol (beta blocker) Timoptic, BlocadrenBetaxolol (beta blocker) BetopticCarteolol (beta blocker) CartrolMetoprolol (beta blocker) LopressorMajor side effects: Diamox: hypotension, drowsiness, paresthesias; for beta blockers local effects
are generally minimal, although clients commonly complain of transient
ocular stinging; occasionally the beta blockers will cause conjunctivitis,
blurred vision, photophobia, and dry eyes.
Treatment: Carbonic anhydrase inhibitors and beta blockers are used to treat glaucoma;
they reduce intraocular pressure (IOP) in chronic open-angle glaucoma by
decreasing the production of aqueous humor; beta blockers reduce
production of aqueous humor by an unknown mechanism; the
beta-adrenergic antagonists, timolol, betaxolol, carteolol, and metoprolol are
first-line drugs for treatment of glaucoma because they cause less disturbance
of vision than pilocarpine and other agents used to treat glaucoma.
Note: The effect of Diamox is due to inhibition of carbonic anhydrase activity in the proximal renal tubule, preventing formation
of carbonic acid. Inhibition of carbonic anhydrase in the eye reduces the rate of aqueous humor formation, with consequent
lowering of intraocular pressure.
Ophthalmic Drugs ◆ 117
◆ Ophthalmic Agents to Increase Aqueous Outflow
Generic Name Trade Name
Physostigmine Antilirium
Pilocarpine Pilocar, others
Epinephrine No common trade name
Dipivefrin PropineTreatment: To reduce IOP in acute open-angle glaucoma and chronic
closed-angle glaucoma by increasing aqueous humor outflow,
especially after iridectomy for treatment of acute closed-angle
glaucoma
Major side effects: Physostigmine: bronchospasm, pulmonary edema, blurred vision,
conjunctivitis, convulsions
Pilocarpine: blurred vision, eye pain, bradycardia, bronchospasm,
hypotension
Epinephrine: eye pain, brow ache, blurred vision, tachycardia,
elevation of blood pressure
Propine: hypertension, tachycardia
Note: Propine is converted to epinephrine by esterase in the eye, but unlike epinephrine, it produces only minimal systemic
sympathomimetic effects.
◆ Ophthalmic Agents Used in Neonates
Generic Name Trade Name
Tetracycline suspension Cyclopar, others
Erythromycin No common trade name
Use: The instillation of a prophylactic agent in the eyes of all
neonates is mandatory in the United States as a precaution
against ophthalmia neonatorum.
Major side effects: Tetracycline: nausea, vomiting, diarrhea, photosensitivity
Erythromycin: nausea, vomiting, diarrhea
Chapter
12Chemotherapy Used toTreat InfectiousDiseases
CHEMOTHERAPY USING ANTI-INFECTIVES
1. Although we often think of chemotherapy as the use of drugs to kill or suppresscancer cells, this term was first defined as the use of chemicals against invadingorganisms (e.g., bacteria, viruses, fungi). Today, it is applied to the treatment ofcancer as well as the treatment of infection. Hence, not only do we speak of cancerchemotherapy, we also speak of chemotherapy for infectious diseases.
2. It has become common practice to use the terms antibiotic and antimicrobial druginterchangeably. We will follow that practice here. However, the formal definitionsof these words are not identical. Antibiotics are actually made by microorganisms;antimicrobial drugs are defined as any agent, natural or synthetic, that has the abilityto kill or suppress microorganisms. From the perspective of therapeutics, there is nobenefit to be gained from distinguishing between drugs made by microorganismsand drugs derived from other sources; hence the current practice of using the termsantibiotic and antimicrobial drug as synonyms.
3. The first rule of antimicrobial therapy is to match the drug with the organism.Therefore, whenever possible, the infecting organism should be identified prior toinitiation of drug therapy.
4. The quickest, simplest technique for identifying microorganisms is microscopicexamination of a gram-stained preparation. Samples for examination can be ob-tained from sputum, blood, urine, pus, and other body fluids.
118
Chemotherapy Used to Treat Infectious Diseases ◆ 119
5. Because of the emergence of drug-resistant organisms, testing for drug sensitivityis common. However, sensitivity testing is only used when the infecting organ-ism is one in which resistance is likely. For example, microbes such as group Astreptococci have remained highly susceptible to penicillin; therefore, sensitivitytesting is unnecessary. In contrast, when resistance is common, as it is with Staphy-lococcus aureus and the gram-negative bacilli, tests for drug sensitivity should beperformed.
6. Use of all antimicrobial drugs promotes the emergence of drug-resistant organ-isms. However, some agents are more likely to promote resistance than others.Since broad-spectrum antibiotics kill more competing organisms than do narrow-spectrum drugs, emergence of resistance is facilitated most by the broad-spectrumdrugs. The more those antibiotics are used, the faster drug-resistant organismswill emerge. Not only do antibiotics promote emergence of resistant pathogens,these drugs also promote overgrowth of normal flora that possess mechanisms forresistance.
7. Since hospitals are sites of intensive antibiotic use, resident organisms can beextremely drug resistant. As a result, nosocomial infections (infections acquiredin hospitals) are among the most difficult to treat.
8. Superinfections are simply an example of the emergence of drug resistance. Asuperinfection is defined as a new infection that appears during the course oftreatment for a primary infection. A new infection can develop because antibioticuse can eliminate the inhibitory influence of normal flora, thereby allowing asecond infectious agent to flourish.
9. Because broad-spectrum antibiotics kill more normal flora than do narrow-spectrum drugs, superinfections are more likely to occur with use of broad-spectrum agents. Superinfections can be difficult to treat, since they are, by defi-nition, caused by microbes that are drug resistant.
NURSING IMPLICATIONS
1. Tetracycline can discolor developing teeth. Use of tetracycline should be avoidedby pregnant women and children less than 8 years of age. Tetracycline can pro-mote bacterial superinfections of the bowel, resulting in diarrhea. Instruct thepatient to notify the physician if diarrhea develops.
2. Erythromycin is generally free of serious toxicity and is one of the safest antibi-otics. It is often prescribed if the patient is allergic to penicillin.
3. Streptomycin may cause damage to the eighth cranial nerve, resulting in hearingloss.
4. The penicillins are nearly ideal antibiotics, and are active against a variety ofbacteria.
a. Allergic reactions constitute their principal adverse effect.
b. Because of their safety and effectiveness, the penicillins are widely prescribed.
120 ◆ Chapter 12
c. Instruct the patient to take oral penicillin with a full glass of water 1 hourbefore or 2 hours after meals. Penicillin V, amoxicillin, and bacampicillinmay be taken with meals.
5. Cephalosporins are bactericidal via inhibition of synthesis of bacterial cell walls.
a. First-generation drugs include cefadroxil and cefazolin. Second-generationdrugs include cefaclor and cefprozil. Third-generation drugs include cefiximeand cefdinir.
b. Major side effects include bone marrow suppression and decreased WBCcount, platelets, and hematocrit. Other side effects include diarrhea, nausea,vomiting, superinfections, abdominal pain, rash, and fever.
c. The nurse should culture infections per the doctor’s orders and arrange forsensitivity tests before beginning drug therapy as well as during therapy if theexpected response is not seen.
6. Administer antimicrobials with food to decrease GI upset and enhance absorp-tion. Assess for signs of superinfections and discontinue the drug if a hypersen-sitivity reaction occurs.
7. Aminoglycosides are bactericidal; they inhibit protein synthesis in susceptiblestrains of gram-negative bacteria by disrupting the functional integrity of thebacterial cell membrane.
a. Representative drugs are neomycin (oral), streptomycin, and tobramycin(parenteral).
b. Major side effects include ototoxicity, nephrotoxicity, hepatotoxicity, andhepatomegaly.
c. The nurse should monitor the duration of treatment. The usual duration is7–10 days. If no clinical response is seen within 3–5 days, stop therapy.Prolonged treatment leads to an increased risk of toxicity. If the drug is usedlonger than 10 days, monitor auditory and renal function daily.
8. Ensure that the patient is well hydrated before and during therapy. Provide smalland frequent meals if nausea or anorexia occur.
9. Macrolides are bacteriostatic or bactericidal in susceptible bacteria. They bind tocell membranes and cause changes in protein function, leading to bacterial celldeath.
a. Representative drugs are azithromycin, clarithromycin, erythromycin, anddirithromycin.
b. Major side effects include reversible hearing loss, uncontrollable emotions,abnormal thinking, abdominal cramping, anorexia, diarrhea, anaphylaxis, andsuperinfection.
c. The nurse should culture sites of infection before therapy per the doctor’sorders.
d. Administer erythromycin base or stearate on an empty stomach, 1 hour beforeor 2–3 hours after meals, with a full glass of water. Oral erythromycin estolate,
Chemotherapy Used to Treat Infectious Diseases ◆ 121
ethylsuccinate, and certain enteric-coated tablets may be given with meals;always check the manufacturer’s instructions.
e. Monitor liver function in patients on prolonged therapy.
10. Fluoroquinolones are bactericidal, interfering with DNA replication in suscepti-ble gram-negative bacteria, preventing cell reproduction and leading to the deathof the bacteria.
a. Representative drugs include ciprofloxacin, levofloxacin, sparfloxacin, andlomefloxacin.
b. Major side effects include headache, dizziness, insomnia, nausea, vomiting,photosensitivity, and elevated BUN, AST, ALT, and serum creatinine.
c. The nurse should arrange for culture and sensitivity testing before beginningtherapy per the doctor’s orders.
d. Administer oral drug 1 hour before or 2 hours after meals with a glass of milk.Administer antacids, if needed, at least 2 hours after dosing aminoglycosides.
e. Monitor clinical responses and if no improvement is seen or a relapse occurs,repeat culture and sensitivity tests.
11. Sulfonamides are bacteriostatic; they competitively antagonize para-aminobenzoic acid in susceptible gram-negative and gram-positive bacteria,causing cell death.
a. Representative drugs include sulfadiazine, sulfamethizole, and sulfamethox-azole.
b. Major side effects include glossitis, stomatitis, proctitis, nausea, diarrhea,vaginitis, and dermatitis.
c. The nurse should arrange for culture and sensitivity tests of infected areasprior to therapy and repeat cultures if the response is not as expected.
d. Ensure adequate fluid intake. Provide small frequent meals if GI upset occurs.
ANTIMICROBIAL DRUGS OF CHOICE
◆ Common First-Line Antimicrobials
Organism Drug of Choice
Penicillin-resistant Streptococcusand methicillin-resistant
S. pneumococci
Zyvox (linezolid)
Staphylococcus aureus Penicillin G or VMethicillin-resistant Vancomycin with or without rifampin
(continued)
122 ◆ Chapter 12
◆ Common First-Line Antimicrobials (continued)
Organism Drug of Choice
Gardnerella vaginalis MetronidazoleLegionella pneumophila
(Legionnaire’s disease)
Erythromycin plus rifampin
Pseudomonas aeruginosa (urinary
tract infection)
Ciprofloxacin
Mycobacterium tuberculosis Isoniazid (INH) plus rifampin; pyrazinamidewith or without ethambutol
Chlamydia trachomatis TetracyclineRocky Mountain spotted fever TetracyclineTreponema pallidum (syphilis) Penicillin GHerpes simplex virus (genital) AcyclovirTreatment of lower respiratory tract
infections and other acute bacterial
exacerbations
Zithromax (azithromycin)
Note: Only a few antimicrobial drugs used to destroy specific organisms are listed. There are many more organisms with a
known drug of choice, but there is no reason for a nurse to know them all.
NURSING IMPLICATIONS
1. Antimicrobial therapy is assessed by monitoring clinical responses and laboratoryresults. The frequency of monitoring is directly proportional to the severity ofinfection.
2. Important clinical indicators of success are reduction of fever and resolution ofsigns and symptoms related to the affected organ system (e.g., improvement ofbreath sounds in patients with pneumonia).
3. Success of therapy is indicated by the disappearance of infectious organismsfrom post-treatment cultures; these cultures may become sterile within hours ofthe onset of treatment (as may happen with urinary tract infections), or they maynot become sterile for weeks (as may happen with tuberculosis).
4. Assess the patient for allergic reactions to antimicrobials, especially during thefirst few days of drug therapy. The allergic reactions and side effects of the anti-infective the patient is receiving may cause signs and symptoms similar to thoseof the infection itself (e.g., nausea, vomiting, diarrhea, abdominal pain). Thenurse should report any of these signs and symptoms after an anti-infective drugis given.
5. Check the patient’s history and laboratory data. Inquire about any previous in-fections that may have occurred (e.g., upper respiratory tract or lower urinarytract infections).
Chemotherapy Used to Treat Infectious Diseases ◆ 123
6. Observe the patient for signs of nosocomial infections.
7. Evaluate the current status of the patient, including signs of renal failure, respi-ratory distress, circulatory congestion, and systemic infection.
8. Note the patient’s nutritional status and current eating habits.
9. Check the type and location of any pain.
10. Note the color, consistency, and amount of urine; antimicrobial therapy can bevery damaging to the liver and renal system.
11. Encourage the adult patient to drink at least 1500–2000 mL of fluid every day;this will help flush the degraded antimicrobial out of the body.
DRUG THERAPY FOR URINARY TRACT INFECTIONS
1. Urinary tract infections (UTIs) are the most common infections encountered today.
2. UTIs may be classified according to their location, in either the lower urinary tractor the upper urinary tract.
3. Within this classification scheme, cystitis and urethritis are considered lower tractinfections.
4. Pyelonephritis is considered an upper tract infection.
ACUTE CYSTITIS
1. Clinical manifestations are dysuria, urinary urgency, and urinary frequency.
2. Causative organisms are Escherichia coli (87%), Staphylococcus saprophyticus(11%), and Streptococcus faecalis (2%).
3. Antibiotics used to treat cystitis include cephalosporins or tetracycline.
4. Because cystitis causes urinary spasms, oxybutynin chloride (Ditropan) maybe used as an antispasmodic agent, or for an overactive bladder (side effect:leukopenia).
5. Cystitis causes pain; therefore, urinary analgesics such as phenazopyridine (Pyrid-ium) should be given. This agent will alleviate the pain and burning sensation thatoccurs during urination. Co-trimoxazole (Septra or Bactrim) may also be used.
6. Side effects of these drugs include thrombocytopenia, agranulocytosis, leukopenia,and hemolytic anemia. Pyridium turns urine red-orange.
URINARY TRACT ANTISEPTICS
Urinary tract antiseptics are drugs for which use is restricted to the treatment of urinarytract infections (UTIs).
124 ◆ Chapter 12
◆ Urinary Tract Antiseptics
Generic Name Trade Name
Nitrofurantoin Furadantin, MacrodantinMethenamine Mandelamine, Urex
Cinoxacin Cinobac
Desired effects: These urinary tract antiseptics are bacteriostatic in low concentrations,
and interfere with bacterial carbohydrate metabolism; they are
bactercidal in high concentrations, disrupting bacterial cell wall
formation and causing cell death.
Major side effects: Common side effects include nausea, vomiting, anorexia, and abdominal
cramps.
Treatment: Urinary tract infections and prevention of urinary tract infections
Nursing implications: Teach patients to take the drug with food or milk; be sure that patients
complete the full course of drug therapy to ensure resolution of the
infection; take this drug at regular intervals around the clock; educate
patients about side effects of the drug and be sure they report any
side effects to their health care provider.
DRUGS FOR SEXUALLY TRANSMITTED DISEASES
CHLAMYDIAL INFECTION
1. Sexually transmitted diseases (STDs) are defined as infectious or parasitic diseasesthat are transmitted primarily through sexual contact.
2. Chlamydia trachomatis is the most common bacterial STD in the United States.
3. About 3 million new cases develop each year. The drug of choice is doxycycline(Vibramycin) or tetracycline (Achromycin) when allergic to penicillin.
4. The recommended first-line treatment for adults and adolescents who have chlamy-dial infections is drug therapy with tetracycline, erythromycin, or azithromycin.The drug of choice for C. trachomatis infection during pregnancy is erythromycin.
a. Although the symptoms are mild and the infection is benign, it causes sterilityin up to 50,000 women each year, primarily from fallopian tube scarring.
TRICHOMONIASIS
1. Trichomoniasis is caused by Trichomonas vaginalis. In women, the infection maybe asymptomatic or may cause a thin, watery vaginal discharge along with burningand itching sensations.
2. In men, the infection is usually symptom free.
Chemotherapy Used to Treat Infectious Diseases ◆ 125
3. Most infections can be eliminated with a single 2-gram dose of metronidazole(Flagyl).
GONOCOCCAL INFECTION
1. Gonorrhea is caused by Neisseria gonorrhoeae.
2. The incidence of gonorrhea is high: about 700,000 cases are reported annually.
3. In men, the main symptoms are a burning sensation while urinating and puslikedischarge from the penis.
4. In contrast, gonorrhea in women is commonly asymptomatic. However, serious in-fection of female reproductive anatomy (vagina, urethra, cervix, ovaries, fallopiantubes) can occur, ultimately resulting in sterility.
5. The drug of choice for uncomplicated gonorrhea is ceftriaxone (Rocephin) admin-istered in a single IM dose (125–250 mg). Other drugs such as penicillin PO arealso effective but there may be an issue with compliance since it may be prescribedfor as long as 10 days. Penicillin is less costly and compliance is not an issue withan injection.
PELVIC INFLAMMATORY DISEASE
1. Acute pelvic inflammatory disease (PID) is a syndrome that includes endometri-tis, pelvic peritonitis, ovarian abscess, and inflammation of the fallopian tubes.Infertility can result.
2. Prominent symptoms are abdominal pain, vaginal discharge, and fever.
3. Most frequently, PID is caused by N. gonorrhoeae and/or C. trachomatis.
4. Because multiple organisms are likely to be involved, drug therapy must providebroad coverage.
5. For the hospitalized client, treatment with IV doxycycline (Vibramycin) can beused in combination with either IV cefoxitin (Mefoxin) or IV cefotetan.
6. This IV therapy is followed by oral therapy with doxycycline (Vibramycin). Theentire course takes 10–15 days.
SYPHILIS
1. Syphilis is caused by the spirochete Treponema pallidum.
2. The incidence of syphilis has increased steadily over the past decade.
3. T . pallidum has remained highly responsive to penicillin G, the drug of choice fortreatment.
4. Early symptoms include a primary lesion, in which one or more chancres (small,fluid-filled lesions) erupt on the genitalia; others may erupt on the anus, fingers,lips, tongue, nipples, tonsils, or eyes. These chancres are usually painless and
126 ◆ Chapter 12
typically disappear after 3–6 weeks, even untreated. Lymph nodes may becomeswollen. Alopecia may occur with or without treatment and is usually temporary.
a. Latent syphilis is characterized by an absence of clinical symptoms, but willhave a reactive serologic test. Because infective mucocutaneous lesions maydevelop for up to 4 years postinfection, the early latent stage is consideredcontagious. Approximately two-thirds of patients remain asymptomatic in thelate latent stage; the rest develop characteristic late-stage symptoms.
b. Late syphilis is the final, destructive noninfectious stage of the disease. It hasthree subtypes, any or all of which may affect the patient: late benign syphilis,cardiovascular syphilis, and neurosyphilis. In late benign syphilis the typicallesion is called a gumma, and it develops on the skin, bone, mucous mem-branes, upper respiratory tract, liver, or stomach between 1 and 10 years afterthe initial infection. The typical lesion is a chronic, superficial nodule or deep,granulomatous lesion that is solitary, asymmetrical, painless, and indurated.Cardiovascular syphilis develops about 10 years after the initial infection inapproximately 10% of patients with late untreated syphilis. It causes fibrosisof elastic tissue of the aorta and leads to aortitis, usually in the ascending andtransverse section of the aortic arch. Cardiovascular syphilis may be asymp-tomatic or may cause aortic insufficiency or aneurysm. Finally, symptoms ofneurosyphilis develop in about 8% of patients with late untreated syphilis, andappear from 5–35 years after infection. The clinical effects consist of menin-gitis and widespread central nervous system damage that may include generalparesis, personality changes, and arm weakness.
c. Confirmation of the diagnosis is done by identifying T. pallidum from a lesionby darkfield microscopic examination. This method is most effective when thelesion is moist. The fluorescent treponemal antibody absorption test identifiesantigen of T. pallidum in tissue, ocular fluid, cerebrospinal fluid (CSF), tracheo-bronchial secretions, and exudates from lesions. This is the most sensitive testfor detecting syphilis in all stages. Once reactive, it remains so permanently.
5. Infants exposed to T. pallidum in utero can be born with syphilis.
6. Signs of congenital syphilis include body sores, rhinitis, and severe tendernessover bones, as well as deafness.
Nursing Implications� Stress the importance of completing the full course of antibiotic therapy, even after
symptoms subside.� Check for a history of drug sensitivity before administering the first antibiotic dose.� In cardiovascular syphilis, check for signs of decreased cardiac output (decreased
urine output, hypoxia, decreased sensorium) and pulmonary congestion.� In neurosyphilis, regularly check the level of consciousness and monitor vital signs.� In late syphilis, provide symptomatic care during prolonged treatment.� Remind patients that safer sex practices and consistent condom use are important
measures in syphilis prevention.
Chemotherapy Used to Treat Infectious Diseases ◆ 127
� Be sure to report all cases of syphilis to local public health authorities. Urge thepatient to inform their sex partners about the infection so that they can also receivetreatment.
HERPES SIMPLEX GENITAL INFECTIONS
1. Symptoms of primary infection develop 6–8 days after contact.
2. In females, blisters or vesicles can appear on the labia, vagina, cervix, and foreskinof the clitoris.
3. In males, vesicles develop on the penis and occasionally on the testicles.
4. Painful urination and watery discharge can occur in both sexes.
5. Patients may experience systemic symptoms, such as fever, headache, myalgia,and tender, swollen lymph nodes in the affected region.
6. Within days, the original blisters can evolve into large, painful, ulcerlike sores.
7. Over the next 2–3 weeks, all symptoms resolve spontaneously.
8. The virus will remain present in a latent state and can cause recurrences.
9. Since there is no cure, symptoms may reoccur for life.
10. Fortunately, subsequent episodes usually become progressively shorter and lesssevere, and in some cases may cease entirely.
11. Transmission of genital herpes infection can occur during the symptomatic periodand for 1 week thereafter.
12. Infected individuals should avoid sexual contact during this time. Use of a con-dom reduces the risk of transmission.
◆ Drugs Used to Treat Genital Herpes
Generic Name Trade Name
Acyclovir ZoviraxValacyclovir Valtrex
Famciclovir sodium FamvirTreatment: Genital herpes
Note: The medications above are antiviral medications used in the treatment of infection and prophylaxis for recurrent genital
herpes infections. There is no cure for genital herpes.
ACQUIRED IMMUNODEFICIENCY SYNDROME
1. The acquired immunodeficiency syndrome (AIDS) is caused by the human im-munodeficiency virus (HIV).
2. Since its identification as a new disease in 1981, AIDS has become a worldwideepidemic, and millions of people are now infected.
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3. AIDS is transmitted sexually and by sharing infected needles. HIV is present inall body fluids of infected individuals.
4. Transmission can be via intimate contact with blood, semen, and vaginalsecretions.
5. The disease can also be transmitted by an accidental needlestick.
6. It can be transmitted to the fetus by an infected mother.
7. HIV can damage many cell types, especially those of the immune and nervoussystems.
8. By attacking cells of the nervous system, the virus can cause dementia andperipheral neuropathies.
9. By attacking the immune system, the virus can greatly compromise the abilityto mount an immune response. As a result, the client develops opportunisticdiseases. Drugs used to treat these AIDS-associated infections are summarizedbelow.
10. Zidovudine (azidothymidine) has been the drug of choice for HIV-infected pa-tients. Zidovudine, formerly known as AZT, is now most often referred to byits trade name (Retrovir). Retrovir is gradually being combined with other newantiviral drugs that have less serious side effects. These drugs, like Retrovir, sup-press viral replication, but do not kill the virus. Accordingly, Retrovir does notoffer a cure, but it can delay onset of symptoms, reduce severity of symptoms,and significantly prolong life.
11. Current medical management for AIDS primarily consists of treatment with acombination of antiviral drugs referred to as a cocktail.
12. The effectiveness of Retrovir therapy or that of any other antiviral drug decreasesover time. Development of drug resistance is believed to cause the decrease ineffectiveness.
13. Combination therapy (use of more than one drug alternatively or simultaneously)is becoming standard practice. Immune suppression occurs as a side effect ofthese drugs and predisposes the client to opportunistic diseases.
◆ Drugs Used to Treat the Acquired ImmunodeficiencySyndrome
Generic Name Trade Name
Nucleoside reverse transcriptase inhibitors (NRTIs)
Tenofovir (TDF) VireadDesired effect: Inhibits reverse transcriptase activity leading to a blocking of HIV
reproduction
Side effects: Severe hepatomegaly, lactic acidosis (sometimes severe), and anorexia
Treatment: HIV infection in combination with other antiretroviral drugs
(continued)
Chemotherapy Used to Treat Infectious Diseases ◆ 129
◆ Drugs Used to Treat the Acquired ImmunodeficiencySyndrome (continued)
Generic Name Trade Name
Tenofovir (continued) VireadNursing implications: Educate female patients to avoid pregnancy while taking this drug; do not take any
other drugs, prescription or over-the-counter, without consulting your health
care provider; report severe diarrhea, changes in color of stool or urine, rapid
respirations
Abacavir (ABC) ZiagenDesired effects: Used in combination with other anti-HIV drugs to reduce the viral load as much as
possible and decrease the chance of further viral mutation
Side effects: Severe to fatal lactic acidosis, severe to fatal hepatomegaly
Nursing implications: Educate patients that this drug has been connected with severe hypersensitivity
reactions, which usually occur early in the use of the drug; educate patients to
keep list of hypersensitivity reactions readily available, to stop the drug if any of
these effects occur, and to notify their health care provider.
Didanosine (ddI) Videx, Videx ECDesired effects: Inhibits replication of HIV, leading to cell death
Side effects: Pancreatitis, hematopoietic depression, hepatotoxicity
Nursing implications: Arrange for lab tests (CBC, SMA-12) before and frequently during therapy;
monitor for bone marrow depression; ensure that the patient swallows Videx
EC whole (do not cut, chew, or crush); monitor patient for signs of
pancreatitis, abdominal pain, elevated enzymes; if such signs are seen, stop
drug and resume only if pancreatitis has been ruled out
Lamivudine (3TC) EpivirDesired effects: Reverse transcriptase inhibition via DNA viral termination and HIV polymerase
Side effects: Pancreatitis, hepatomegaly, pancreatitis, peripheral neuropathy
Nursing implications: Arrange to monitor hematologic indices and liver function every 2 weeks during
therapy; severe hepatomegaly with steatosis has occurred.
Stavudine (d4T) ZeritDesired effects: Antiretroviral drug that inhibits replication of some retroviruses
Side effects: Pancreatitis, hepatomegaly, severe anemia, lactic acidosis
Nursing implications: Take the drug every 12 hours; take the extended-release form once each day; this
drug should be used during pregnancy only if the potential benefit justifies the
potential risk
Zalcitabine (ddC) HividDesired effects: Inhibits cell protein synthesis and leads to cell death without viral replication
Side effects: Severe hepatomegaly, pancreatitis, peripheral neuropathy
Nursing implications: Educate the patient to take the drug every 8 hours around the clock; use an alarm
clock to wake up at night to take medication; rest periods during the day may be
needed; arrange for frequent blood tests; results of blood counts may indicate
that the dosage needs to be decreased or the drug discontinued temporarily
(continued)
130 ◆ Chapter 12
◆ Drugs Used to Treat the Acquired ImmunodeficiencySyndrome (continued)
Generic Name Trade Name
Zidovudine (AZT) RetrovirDesired effects: Inhibits HIV replication in both T cells and monocytes
Side effects: Agranulocytopenia, severe anemia requiring transfusions, dyspnea, fever,
severe anemia, anorexia
Treatment: HIV infection in combination with other antiretroviral drugs
Nursing implications: Take the drug every 4 hours around the clock using an alarm clock to wake up
at night to take medication; rest periods during the day may be needed;
arrange for blood test; results of blood counts may indicate that the dosage
needs to be decreased or the drug discontinued temporarily; report extreme
fatigue, lethargy, severe nausea, difficulty breathing
Emtricitabine (FTC) EmtrivaDesired effects: Inhibits HIV replication via reverse transcriptase inhibition
Side effects: Nausea, diarrhea, headache, rash, darkening of the skin of the palms and soles
of the feet; hepatomegaly with steatosis sometimes seen; pancreatitis
Treatment: HIV infection in combination with other antiretroviral drugs
Nursing implications: Pancreatitis can be life threatening; monitor blood tests for pancreatitis and stop
the drug and contact the physician if signs of pancreatitis are seen.
Non-nucleotide reverse transcriptase inhibitors (NNRTIs)
Delavirdine (DLV) RescriptorDesired effects: Inhibitor of HIV reverse transcriptase; binds directly to HIV reverse
transcriptase and blocks DNA-dependent and DNA-independent
polymerase
Major side effects: Increased liver enzymes, anorexia, malaise, diarrhea, headache, anemia, rash
Efavirenz (EFV) SustivaDesired effects: Shown to be effective in suppressing the HIV virus in adults and children
Side effects: Dizziness, drowsiness, anorexia
Nursing implications: Arrange to monitor hematologic indices every 2 weeks; ensure that the patient
is taking this drug as part of a combination therapeutic regimen; monitor for
signs of opportunistic infections that will need to be treated appropriately;
establish safety precautions if CNS effects occur, which are especially likely
during the first few days of treatment.
Nevirapine (NVP) ViramuneDesired effect: Blocks the action of reverse transcriptase
Side effects: Liver dysfunction, infection, diarrhea
Treatment: HIV infection in combination with other antiretroviral drugs
Protease inhibitors (PIs)(continued)
Chemotherapy Used to Treat Infectious Diseases ◆ 131
◆ Drugs Used to Treat the Acquired ImmunodeficiencySyndrome (continued)
Generic Name Trade Name
Amprenavir (APV) AgeneraseDesired effects: Inhibits HIV infection in combination with other antiretroviral agents
Side effects: Hyperglycemia, hypertriglyceridemia, anorexia, peripheral paresthesias
Nursing implications: Do not take this drug with a high-fat meal and do not drink grapefruit juice
while on this drug.
Indinavir (IDV) CrixivanDesired effects: Inhibits HIV protease activity, leading to production of immature
noninfective HIV particles
Side effects: Hyperbilirubinemia, hematuria, nocturia, headache, palpitations, diarrhea,
dysuria, anorexia
Nursing implications: Take this drug on an empty stomach 1 hour before or 2 hours after a meal,
with a full glass of water; if GI upset is severe, take with a light meal;
avoid grapefruit juice and foods high in calories, fat, or protein; store
capsules in the original container because they are very sensitive to
moisture.
Nelfinavir (NFV) ViraceptDesired effects: Prevents viral cleavage, resulting in the production of immature
noninfectious viruses
Major side effects: Seizures, diarrhea, liver enzyme elevation, anorexia, diarrhea, dyspnea,
sexual dysfunction
Nursing implications: Administer drug with a meal or a light snack; powder may be mixed with a
small amount of non-acidic food or beverage; use within 6 hours of
mixing; monitor patient for signs of opportunistic infections that will
need to be treated appropriately.
Ritonavir (RTV) NorvirDesired effects: Inhibits HIV protease activity, leading to a decrease in production of HIV
particles
Side effects: Anxiety, hematuria, apnea, anorexia, liver dysfunction, diarrhea
Nursing implications: Take the drug with meals or food; refrigerate capsules; the taste of the
solution may improve if mixed with chocolate milk, Ensure, or Advera
1 hour before taking; do not drink grapefruit juice while using this drug.
Saquinavir (SQV) InviraseDesired effects: Protease inhibitor, which in combination with nucleoside analogues is
effective in treating HIV infections with changes in surrogate markers
Side effects: Anorexia, insomnia, paresthesias, headache, elevated CPK, elevated
triglycerides and cholesterol; fat redistribution may occur (central
obesity, buffalo hump, cushingoid appearance)
Saquinavir (SQV) FortovaseDesired effect: Keeps infected cells from producing new mature viruses
(continued)
132 ◆ Chapter 12
◆ Drugs Used to Treat the Acquired ImmunodeficiencySyndrome (continued)
Generic Name Trade Name
Saquinavir (SQV) (continued) FortovaseSide effects: Headache, insomnia, malaise, dizziness, paresthesias, fatigue
Nursing implications: Take drug within 2 hours of a full meal; take concurrently with other
prescribed medications; do not drink grapefruit juice while using this
drug; store drug in refrigerator; use by expiration date
Atanzavir (ATV) ReyatazDesired effect: Keeps infected cells from producing new mature viruses
Side effects: Hyperbilirubinemia, prolonged PR interval; first-degree A-V block
Nursing implications: Take drug with food; take concurrently with other prescribed medications;
take the drug 2 hours before or 1 hour after antacids or didanosine;
swallow the capsules whole (do not chew or crush)
Fosamprenavir (f-APV) LexivaDesired effect: Keeps infected cells from producing new mature viruses
Side effects: Skin rash, GI intolerance, headache
Nursing implications: Take drug with or without food, but always with a full glass of water; take
the drug 21/2 hours before or after didanosine
Lopinavir + ritonavir (LPV/r) KaletraDesired effect: Keeps infected cells from producing new mature viruses
Side effects: GI intolerance, headache, weakness, asthenia, increased liver function
tests, pancreatitis
Nursing implications: Take drug with food; take concurrently with other prescribed medications;
store capsules in the refrigerator
Note: Retrovir has the most serious side effects, which include anemia and neurotoxicity.
◆ Agents Used to Treat AIDS-Related Opportunistic Diseases
Generic Name Trade Name
Co-trimoxazole Bactrim, SeptraPentamidine No commonly used trade name
Sulfisoxazole GantrisinFluconazole DiflucanAmphotericin B Fungizone
Interferon beta-1b Betaseron• Bactrim, Septra
Nursing implications: This drug should not be administered to patients with severe renal failure, hepatic
disease, or hypersensitivity to sulfonamides; educate patients about its side
effects, including anorexia, nausea, vomiting, fatigue, depression, stomatitis,
depression, headache, vertigo, and photosensitivity.
Chemotherapy Used to Treat Infectious Diseases ◆ 133
◆ Agents Used to Treat AIDS-Related OpportunisticDiseases (continued)
Generic Name Trade Name
• Pentamidine
Nursing implications: This is used in the treatment (IM or IV) and prevention (inhalational) of
Pneumocystis carinii pneumonia; inform patients of side effects, including
tachycardia, hypotension and hypertension, syncope, shortness of breath,
bronchospasm, and laryngospasm; have frequent blood tests and blood
pressure checks, because this drug may cause many changes in the body.
• Gantrisin
Nursing implications: Used for acute infections caused by susceptible organisms; it is CDC
recommended for treatment of sexually transmitted diseases; it is also used for
other diseases (e.g., UTIs, chancroid, inclusion conjunctivitis, trachoma,
nocardiosis, toxoplasmosis); teach patients side effects of the drug, including
headache, peripheral neuropathy, depression, photosensitivity, nausea,
vomiting, crystalluria, hematuria, and agranulocytosis; teach patients to take the
drug on an empty stomach, 1 hour before or 2 hours after meals, with a full
glass of water; arrange for culture and sensitivity tests before therapy; repeat
cultures if response is not as expected.
• Fluconazole
Nursing implications: Used in the treatment of oropharyngeal, esophageal, vaginal, and systemic
candidiasis, cryptococcal meningitis, and prophylaxis for candidiasis in bone
marrow transplants; teach patient side effects of headache, nausea, vomiting,
diarrhea, abdominal pain, and AST/ALT elevations; culture before therapy;
begin treatment before lab results are returned; decrease dosage in cases of
renal failure; infuse IV only; not intended for IM or subcutaneous injections
• Amphotericin B
Nursing implications: This drug is reserved for patients with progressive, potentially fatal infections
(e.g., cryptococcosis, cryptococcal meningitis); teach patient side effects of
drug: fever (often with shaking chills), headache, generalized pain,
hypokalemia, azotemia, hyposthenuria, renal tubular acidosis,
nephrocalcinosis, normochromic normocytic anemia, pain at the injection site
with phlebitis and thrombophlebitis; long-term use of this drug will be
needed; beneficial effects may not be seen for several weeks; the systemic
form of the drug can only be given IV; for topical application, apply liberally
to affected area after first cleaning the area; educate patients to report pain or
irritation at the injection site, GI upset, loss of appetite, difficulty breathing,
and other side effects to health caregiver.
Nursing implications: Assess allergy to interferon beta or any component of the product. Obtain
laboratory test (CBC, differential granulocytes and hairy cells, bone marrow
hairy cells, and liver function tests) before therapy and monthly during
therapy. Monitor for severe drug reactions; notify physician immediately;
you may need to reduce dosage or discontinue drug. Ensure that patient is
well hydrated, especially during initiation of treatment. Because depression is
a side effect of this drug, monitor for mental disorder or suicidally
tendencies. Drug should not be used in pregnancy.
(continued)
134 ◆ Chapter 12
◆ Agents Used to Treat AIDS-Related OpportunisticDiseases (continued)
Generic Name Trade Name
Interferon beta-1b BetaseronNursing implications:
for opportunistic
diseases
AIDS-related Kaposi’s sarcoma, metastatic renal carcinoma, malignant melanoma;
teach patient side effects (e.g., hypocalcemia, leukopenia, neutropenia,
thrombocytopenia, anemia, decreased hemoglobin, increased levels of AST,
LDH, alkaline phosphatase, bilirubin, uric acid, serum creatinine, BUN, blood
sugar, serum phosphorus; keep a chart of injection sites to prevent overuse of
one area; arrange for proper disposal of needles and syringes; educate female
patients to use contraceptives during drug therapy; teach patients to report side
effects to their health caregiver and to use sunscreen and wear protective clothing
if exposed to the sun because the drug makes the skin sensitive to the sun.
TUBERCULOSIS INFECTION
1. Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis,an organism also known as the tubercle bacillus.
2. Infections may be limited to the lungs or may be disseminated to other areas suchas bone.
3. In the United States, approximately 10 million people harbor tubercle bacilli.
4. In most cases the bacteria are dormant and the infected individual is free ofsymptoms.
5. When the disease is active, morbidity can be significant; about 2000 Americansdie from tuberculosis annually.
6. After years of being on the decline, the number of reported cases of tuberculosisis now increasing.
7. This increase is attributed to infection in people with AIDS and to the failure ofclients with TB to complete their TB therapy, which should last from 9 monthsto a year. When a client with TB no longer has symptoms, he or she may believethat they are cured and discontinue drug therapy. This has caused mycobacteria todevelop resistance to isoniazid.
CHEMOTHERAPY FOR ACTIVE TUBERCULOSIS
1. A variety of regimens have been employed to treat active tuberculosis.
2. Drug selection is based largely on drug susceptibility of the infecting organismand on the immunocompetence of the host.
3. Most regimens contain isoniazid (INH) plus rifampin.
4. Three modes are employed to evaluate therapy: chest x-ray, bacteriologic evalu-ation of sputum, and clinical evaluation.
Chemotherapy Used to Treat Infectious Diseases ◆ 135
5. In order to eliminate tuberculosis, it is essential that individuals with asymp-tomatic infections are detected and treated. Detection is accomplished byscreening.
6. It is recommended that all high-risk persons be screened. This group includesthose with HIV infection, health care workers, and those with other risk factorsfor tuberculosis, such as chronic renal failure, hematologic malignancy, and useof immunosuppressive drugs.
7. The screen most often employed is the tuberculin skin test. The test is performedby giving an intradermal injection of a protein derived from mycobacteria. Theprotein is referred to as purified protein derivative (PPD; Mantoux test). Thetest is read 48–72 hours after injection.
8. In people harboring tubercle bacilli, injection of PPD can elicit a local hyper-sensitivity reaction. A positive reaction is indicated by the size of the zone ofinduration (hardness).
9. If an individual has a positive tuberculin skin test or clinical manifestationsthat suggest tuberculosis, diagnostic testing for tuberculosis should be done. Adefinitive diagnosis is made with microbiologic evaluation of sputum.
10. Because M. tuberculosis grows very slowly, results of sputum cultures are oftendelayed (by as long as 3–6 weeks). However, with newer culturing techniques,results can be obtained in less than 1 week.
11. The conventional culture method known as the acid-fast bacillus (AFB) testis less sensitive, but equivalent in specificity to, the newer polymerase chainreaction (PCR) test. PCR is a simple tool for amplifying a single nucleic acidsequence of DNA or RNA material to detect and identify the microorganism orgene in question. Detection of TB with PCR yields results in 1 day.
◆ Drugs Used to Treat Tuberculosis
Generic Name Trade Name
Tuberculostatic agents
Isoniazid (INH) No common trade name
Ethionamide Trecator-SCPyrazinamide No commonly used trade
Ethambutol HCl MyambutolTuberculostatic and antibiotic agents
Rifampin No commonly used trade name
Rifapentine PriftinCycloserine Seromycin Pulvules
Capreomycin Capastat Sulfate
Antibiotic agent
(continued)
136 ◆ Chapter 12
◆ Drugs Used to Treat Tuberculosis (continued)
Generic Name Trade Name
Streptomycin No commonly used trade name
Desired effect: Antituberculostatic
Major side effects: • Isoniazid: peripheral neuropathy, blood disorders, vitamin B6 deficiency, jaundice,
fatal hepatitis
• Trecator-SC: depression, drowsiness, peripheral neuritis, anorexia, nausea, vomiting,
metallic taste, stomatitis
• Pyrazinamide: thrombocytopenia, adverse effects on clotting and vascular integrity,
hepatotoxicity, nausea, vomiting
• Myambutol: Optic neuritis (loss of vision acuity change in color perception, fever
malaise, headache, mental confusion disorientation, hallucination peripheral neuritis
joint pain thrombocytopenia, and acute gout.
• Rifampin: headache, drowsiness, fatigue, dizziness, rash, heartburn, epigastric
distress, elevation of liver enzymes
• Priftin: headache, dizziness, pyuria, proteinuria, hyperuricemia, liver enzyme
elevation, nausea, vomiting, reddish discoloration of body fluids
• Cycloserine: seizures, drowsiness, somnolence, headache, tremor, vertigo,
confusion, rash, elevated serum transaminase levels
• Capastat Sulfate: Tachycardia, angina pectoris, MI, Raynaud’s syndrome, CHF,
hypotension renal insufficiency, renal failure, oliguria, urinary frequency, and
thrombocytopenia.
• Streptomycin: lethargy, confusion, depression, oliguria, nausea, vomiting, diarrhea,
hepatotoxicity, renal toxicity, hematologic toxicity, glucose intolerance, azotemia,
nephrotoxicity, blood disorders, eighth cranial nerve damage
Treatment: Antituberculostatic drugs used in the treatment of TB are divided into three categories:
first-line drugs, second-line drugs, and third-line drugs; first-line drugs (isoniazid
[INH], rifampin [RIF], ethambutol [EMB], pyrazinamide, Priftin) are considered more
effective and less toxic than the second-line drugs; second-line drugs include
cycloserine, Trecator-SC, and streptomycin; third-line drugs include capreomycin
and ethionamide.
Latent TB is usually treated with daily INH for 9 months. RIF daily for 4 months may be
used for latent TB if bacteria show resistance to INH; for most adults with active TB,
the recommended dosing includes the administration of four drugs daily for 2
months, followed by 4 months of INH and RIF.
Drug therapy must be selected according to the patient’s condition and the organism’s
susceptibility; second- and third-line drugs are reserved for drug-resistant strains;
interruption of drug therapy may require initiation of therapy from the beginning of
the regimen or additional treatment.
Directly observed therapy (DOT) may be selected or required; in this type of therapy
an assigned caregiver directly observes the administration of the drugs; the goal of
DOT is to monitor the treatment regimen to assure compliance and to reduce the
development of resistant organisms.
Advise staff members and other persons who have been exposed to infected patients
to receive tuberculin testing; chest x-rays and prophylactic INH may also be ordered;
visitors and staff members should wear particulate respirator masks that fit closely
around the nose and mouth when they are in the room with infected patients.
(continued)
Chemotherapy Used to Treat Infectious Diseases ◆ 137
◆ Drugs Used to Treat Tuberculosis (continued)
Generic Name Trade Name
Nursing implications: Be alert for adverse effects of the medications; because INH use sometimes
leads to hepatitis or peripheral neuritis, to prevent or treat peripheral neuritis
give the patient pyridoxine (vitamin B6) as ordered.
AGENTS USED IN THE PREVENTION OF HEPATITIS B
◆ Drugs Used to Stimulate an Immunologic Response toHepatitis and Haemophilus influenzae
Generic Name Trade Name
Hepatitis B vaccine Recombivax HB, Engerix-BHepatitis A vaccine, inactivated Havrix, VaqtaInactivated hepatitis A and
hepatitis B recombinant vaccine
Twinrix
Haemophilus b conjugate vaccine Liquid PedvaxHIBHaemophilus b conjugate vaccine
with hepatitis B surface antigen
(recombinant)
Comvax
Hepatitis B immuneglobulin (HBIG)
BayHep B, Nabi-HB
Nursing implications: There is no specific drug treatment for hepatitis, with the
exception of hepatitis C, which has been treated somewhat
successfully with alpha interferon; instead, patients are advised
to rest in early stages of the illness and to combat anorexia by
eating small, high-calorie, high-protein meals; protein intake
should be reduced if signs or symptoms of pre-coma lethargy,
confusion, and mental changes develop; provide rest periods
throughout the day; schedule treatments and tests so the patient
can rest between activities.
Therapeutic effects: Recombivax HB immunizes against infections caused by all known
subtypes of hepatitis B virus, especially those seen in high-risk
health caregivers, military personnel identified to be at risk,
prisoners, users of illicit drugs, populations with a high incidence
of TB (Eskimos, Indochinese refugees, Haitian refugees),
morticians and embalmers, persons at risk because of their sexual
practices, patients requiring frequent blood transfusions,
residents in mental institutions, all infants, adolescents 11–12
years of age, and older unvaccinated adolescents at high risk.
(continued)
138 ◆ Chapter 12
◆ Drugs Used to Stimulate an Immunologic Response toHepatitis and Haemophilus influenzae (continued)
Generic Name Trade Name
Major side effects: Malaise, fatigue, weakness, headache, soreness, erythema, tenderness,
dizziness, low-grade fever, rhinitis, lymphadenopathy, hypotension,
anaphylactic reaction
Warning: Have epinephrine 1:1000 immediately available at the time of injection in case
of severe anaphylactic reaction
Therapeutic effects: Inactivated hepatitis A vaccine (Havrix, Vaqta) contains hepatitis A antigen
that stimulates production of specific antibodies against hepatitis A, which
protects against HAV infection; the immunity does not protect against
hepatitis caused by other agents.
Inactivated hepatitis A and hepatitis B recombinant vaccine (Twinrix)
provides inactivated hepatitis A antigens that stimulate production of
specific antibodies against hepatitis A, which protect against hepatitis A,
and inactivated hepatitis B surface antigen particles, which stimulate active
immunity and production of antibodies against hepatitis B surface antigens.
Haemophilus b conjugate vaccine (Liquid PedvaxHIB) provides
immunization against Haemophilus influenzae type b, and stimulates an
immunologic response in children, leading to active immunity against H.influenzae.
Haemophilus b conjugate vaccine with hepatitis B surface antigen (Comvax)
provides hepatitis B and Haemophilus type b vaccines to stimulate an
immunologic response in children, leading to active immunity against these
diseases.
Hepatitis B immune globulin (HBIG) contains a high titer of antibody to
hepatitis B surface antigen, providing passive immunity to hepatitis B.
ANTIFUNGAL AGENTS
1. Amphotericin B (Fungizone) is active against a broad spectrum of pathogenic fungiand is the drug of choice for most systemic mycoses (i.e., any disease induced bya fungus).
2. Amphotericin B is highly toxic; renal damage is a major concern.
3. For treatment of systemic mycoses, amphotericin B is almost always administeredby IV infusion.
4. Ketoconazole (Nizoral) is an oral alternative to amphotericin B for treatment ofless severe mycoses. This drug is less effective than amphotericin B, and has theadditional advantage of being available in an oral form.
5. Ketoconazole is also active against superficial Candida infections.
6. Responses to ketoconazole are slow.
Chemotherapy Used to Treat Infectious Diseases ◆ 139
◆ Drugs for Mycoses
Generic Name Trade Name
Amphotericin B Fungizone
Ketoconazole NizoralNystatin Mycostatin
Miconazole nitrate Monistat 3, Monistat 7 (vaginal suppositories, topical)
• Amphotericin B
Treatment: Amphotericin B is reserved for patients with progressive, potentially fatal
infections, such as cryptococcosis, North American blastomycosis,
disseminated moniliasis, and coccidioidomycosis, and infections by
Mucor, Rhizopus, Absidia, Entomophthorales, Basidiobolus,sporotrichosis, and Aspergillus; it is also useful in treating cryptococcal
meningitis in HIV-infected patients, and treatment of any kind of
progressive fungal infection that does not respond to other treatment.
Major side effects: Fever (often with shaking chills), headache, malaise, general pain, nausea,
vomiting, normochromic normocytic anemia, renal failure, hypokalemia,
azotemia, hyposthenuria, tubular acidosis, nephrocalcinosis
• Mycostatin
Treatment: Oral: oropharyngeal candidiasis
Vaginal: local treatment of vaginal candidiasis (moniliasis)
Topical: treatment of cutaneous or mucocutaneous mycotic infections caused
by Candida albicans and other Candida species
Major side effects: Nausea, vomiting, vaginal irritation, vulvovaginal burning, local irritation
• Ketoconazole
Treatment: Ketoconazole is active against the fungi that cause superficial infections caused
by Candida species; Nizoral is an oral alternative to amphotericin B for
treatment of less severe systemic mycoses; this drug is less effective than
amphotericin B and responses to ketoconazole are slow.
Major side effects: Ketoconazole: hepatotoxicity, rash, itching, fever, chills, diarrhea
Monistat 3
Monistat 7
Treatment: Vaginal suppositories: Local treatment of vulvovaginal candidiasis (moniliasis)
Topical administration: Tinea pedis, tinea cruris, tinea corporis caused by
Trichophyton rubrum, Trichophyton mentagrophytes, cutaneous candidias
(moniliasis), tinea versicolor.
Major side effect: Vaginal suppositories: irritation, sensitization or vulvovaginal burning, pelvic
cramps
Others: Rash, headache; Topical application: Irritation, burning maceration,
allergic contact dermatitis
Note: Nystatin is safer than amphotericin B and has the additional advantage of being orally available.
140 ◆ Chapter 12
ANTIVIRAL AGENTS
1. Several antiviral agents are approved for use in the United States.
2. These drugs are active against a narrow spectrum of viruses and their clinicalapplications are limited to specific viral infections.
3. Acyclovir (Zovirax) is the agent of first choice for infections caused by herpessimplex viruses, varicella zoster virus, and cytomegalovirus.
4. Acyclovir can be administered orally, intravenously, or topically.
5. Serious side effects are uncommon.
6. Zidovudine (Retrovir), formerly called azidothymidine (AZT), is used with otherantiviral drugs to treat clients infected with the human immunodeficiency virus(HIV), the causative agent of acquired immunodeficiency syndrome (AIDS).
a. Retrovir inhibits HIV replication by suppressing synthesis of viral DNA.
7. Didanosine (Videx), also known as dideoxyinosine or ddI, is approved for clientswith advanced HIV infection who cannot tolerate zidovudine (Retrovir), or haveexperienced significant deterioration despite zidovudine therapy.
8. Zalcitabine (Hivid), also known as dideoxycytidine or ddC, is approved for com-bined use with zidovudine and other antiviral drugs to treat clients with advancedHIV infection.
9. Ganciclovir (Cytovene) is a synthetic antiviral agent with activity against herpesviruses, including cytomegalovirus.
◆ Antiviral Agents
Generic Name Trade Name
Acyclovir ZoviraxZidovudine Retrovir (formerly called AZT)
Didanosine Videx (also known as dideoxyinosine, ddI)
Zalcitabine Hivid (also known as dideoxycytidine, ddC)
Ganciclovir CytoveneValacyclovir ValtrexRibavirin VirazoleTreatment: • Acyclovir: herpes simplex and varicella zoster virus (chickenpox)
• Retrovir: HIV (AIDS)
• Videx: HIV (AIDS)
• Hivid: HIV (AIDS)
• Cytovene: cytomegalovirus
• Valtrex: Herpes zoster (shingles); genital herpes in HIV patients, & cold
sores (herpes labialis)
• Virazole:
Respiratory syncytial virus infection (RSV), influenza virus
Chemotherapy Used to Treat Infectious Diseases ◆ 141
◆ Antiviral Agents (Continued)
Generic Name Trade Name
Side effects: Acyclovir: generally well tolerated; the most common side effects are phlebitis
and inflammation at the infusion site and reversible nephrotoxicity.
• Retrovir: severe anemia and granulocytopenia (abnormal reduction in granular
leukocytes) are the principal toxic effects.
• Videx: pancreatitis and bone marrow depression which can be fatal
• Hivid: the major toxicities are peripheral neuropathy and less commonly
pancreatitis.
• Cytovene: the adverse effect of greatest concern is bone marrow suppression,
which results in granulocytopenia (40%) and thrombocytopenia (20%).
• Valtrex
Adverse effect: Herpes zoster (shingles) and cold sores (herpes labialis) and
herpes
• Virazole
Adverse effects: Depression, suicidal behavior, cardiac arrests, pneumothorax,
bacterial pneumonia, hypotension, deteriorating respiratory function.
PROTOZOAL INFECTIONS
1. Pneumocystis carinii pneumonia is caused by Pneumocystis carinii; its classifica-tion is as both a protozoa and a fungus.
2. The incidence of Pneumocystis carinii pneumonia is extremely high (80%) inclients with AIDS.
3. The treatment of choice for clients who are severely immunocompromised ispentamidine.
4. The treatment of choice for other clients is trimethoprim (Proloprim) plus sul-famethoxazole (Gantanol).
5. Toxoplasmosis is caused by infection with Toxoplasma gondii, a protozoan.
a. The parasite is harbored by many animals as well as by humans.
b. Infection is acquired most commonly by eating undercooked meat or fromcontaminated feces from infected cats. Toxoplasmosis may also be congenital.
c. The treatment of choice is pyrimethamine (Daraprim) combined with a sulfon-amide.
6. Trichomoniasis is caused by Trichomonas vaginalis, a protozoan.
a. Trichomoniasis is a common disease, affecting about 200 million people world-wide.
b. The usual site of infection is the genitourinary tract. Parasites may also inhabitthe rectum.
c. In females, infection results in vaginitis.
142 ◆ Chapter 12
d. In males, infection results in urethritis.
e. The disease is usually transmitted sexually, but can also be acquired by contactwith contaminated objects (e.g., toilet seats).
f. Treatment of choice is metronidazole (Flagyl).
ECTOPARASITICIDES
1. Ectoparasites are parasites that live on the surface of the host.
2. Most ectoparasites that infest humans live on the skin and hair.
3. Some live on clothing and bedding, moving to the host only to feed.
4. The principal ectoparasites that infest humans are mites and lice.
5. Infestation with lice is known as pediculosis.
6. Infestation with mites is known as scabies.
7. Both conditions produce intense pruritus (itching).
8. Infestations with mites and with lice can be eradicated with topical drugs.
SCABIES
1. Scabies are caused by infestation with Sarcoptes scabiei, an organism knowncommonly as the itch mite.
2. Irritation occurs as a result of the female mite burrowing beneath the skin to layeggs.
3. The drug of choice to kill mites is permethrin (Elimite) (5% cream formulation).Lindane (G-Well) is also used to kill mites.
PEDICULOSIS
1. Pediculosis is a general term referring to infection with any of several kinds oflice.
2. The type of lice encountered most frequently are Pediculus humanus capitis (headlouse) and Pthirus pubis (pubic or crab louse).
Pubic Lice
1. Pubic lice, commonly known as crabs, usually reside on the skin and hair of thepubic region.
2. Crabs are most common among people who have multiple sexual partners.
3. The treatment of choice is lindane (G-Well) and malathion (0.5% Prioderm lotion).
Chemotherapy Used to Treat Infectious Diseases ◆ 143
Head Lice
1. Head lice reside on the scalp and lay their nits (eggs) on the hair shafts.
2. Head lice may be transmitted by close personal contact and by contact with infestedclothing, hairbrushes, and other objects.
3. The drug of choice is benzene hexachloride, which is toxic to mites, lice, and theirova. Other drugs used are:
a. Malathion (0.5% Prioderm lotion) kills head lice and ova. Note that this drug isflammable; a hair dryer cannot be used and the client should not smoke whileapplying the drug to wet hair.
b. Lindane (G-Well) is considered both a scabicide and a pediculicide because itis effective in the treatment of both lice and mite infestations. It is available in1% cream, lotion, and shampoo.
Chapter
13Anticancer Drugs
1. Anticancer drugs are toxic to normal tissues, especially to tissue that has a highpercentage of proliferating cells (e.g., bone marrow, hair follicles, gastrointestinalepithelium, germinal cells).
2. The three major modalities for treating cancer are surgery, radiotherapy, andchemotherapy (drug therapy).
3. Surgery and/or irradiation are preferred for most solid cancers.
4. Drug therapy is the treatment of choice for disseminated cancers (leukemias) andwidespread metastases.
5. Drug therapy is also used as an adjunct to surgery and irradiation by killing malig-nant cells that surgery and irradiation leave behind. Adjuvant cancer chemotherapycan significantly prolong life.
6. Cancers with a high cure rate include Hodgkin’s disease, Ewing’s sarcoma, andacute lymphocytic leukemia.
7. At this time, the major impediment to successful chemotherapy is toxicity ofanticancer drugs to normal tissue.
8. Researchers have created a cancer “smart bomb” that attacks and kills leukemiacells in mice without harming normal cells. Dr. F.M. Uckum of the University ofMinnesota–Minneapolis reported that the “smart bomb” is actually an antibodythat will attach to a receptor molecule found only on the surface of leukemiacells. “The antibody is the missile,” said Uckum, “and hooked to the missile isthe payload—a chemical that actually kills the leukemia cell. Normal tissue isnot affected; only the leukemia cells are going to die.” Uckum, the first authorof a study appearing in the Journal of Science, March 1995, wrote that his teamis beginning laboratory tests of the “smart bomb” technique against breast andovarian cancers, but results are still years away. “There are certain substances in
144
Anticancer Drugs ◆ 145
breast cancer that you can target,” he said. “If you do the targeting right, you cankill the breast cancer cells without killing normal cells.”
9. Characteristics of neoplastic cells (cancer cells) are unrestrained growth and divi-sion. The capacity for persistent proliferation is the most distinguishing propertyof malignant cells.
10. In the absence of intervention, cancerous tissues will continue to grow until theycause death. Malignant cells are unresponsive to the feedback mechanisms thatregulate cellular proliferation in healthy tissue.
11. Metastases are secondary tumors that appear at sites distant from the primarytumor. Metastases result from the unique ability of malignant cells to break awayfrom their site of origin, migrate to other parts of the body (via the lymphatic andcirculatory system), and then reimplant to form a new cancerous tumor.
12. The abnormal behavior of cancer cells results from alterations in their DNA. Thesegenetic alterations are caused by chemical carcinogens, viruses, and radiation(x-ray, radioisotopes, ultraviolet light).
13. Early detection of cancer is rare; at this time cancer of the cervix, which can bediagnosed with a Pap smear and is confirmed by biopsy, is the only neoplastic dis-ease capable of truly early diagnosis. All other cancers are significantly advancedby the time they have grown large enough for discovery.
14. During the course of chemotherapy, cancer cells can develop resistance to thedrugs used against them.
15. Use of anticancer agents favors the growth of drug-resistant cells; as therapyproceeds, the number of resistant cells will increase.
16. Because resistant cells cannot be killed with drugs, the risk of therapeutic failureincreases with each course of therapy.
17. Since patients are usually exposed to drug therapy over an extended period, ther-apeutic failure owing to drug resistance is a significant problem.
18. The anticancer drugs fall into two major classes: cytotoxic agents and hormonesand hormone antagonists.
◆ Anticancer Drugs: Cytotoxic Agents
Generic Name Trade Name
Alkylating nitrogen mustards
Cyclophosphamide CytoxanMechlorethamine MustargenAlkylating nitrosoureas
Carmustine BiCNU
Streptozocin ZanosarAlkylating platinum
Cisplatin • Platinol
146 ◆ Chapter 13
◆ Anticancer Drugs: Cytotoxic Agents (continued)
Generic Name Trade Name
Antimetabolite
Methotrexate FolexPyrimidine analogue
Cytarabine Cytosar-UFluorouracil • Adrucil
Purine analogues
Mercaptopurine PurinetholPentostatin NipentAntitumor antibiotics
Doxorubicin AdriamycinMitoxantrone NovantronePlicamycin MithracinMitotic inhibitors
Vinblastine VelbanVincristine OncovinMiscellaneous
Asparaginase • Elspar
Hydroxyurea • Hydrea
Procarbazine • Matulane
Treatment: Cancer
Major side effects: Marrow depression, neutropenia (a severe reduction in white blood cell count),
and a reduction in platelet count; infections secondary to neutropenia are the
most serious complications of cancer chemotherapy; with most anticancer
drugs onset of neutropenia is rapid; a normal white cell count ranges from
2500–7000/mm3; if neutropenia is substantial (absolute neutrophil count
below 500/mm3), the next round of chemotherapy should be delayed until
neutrophil counts return to normal; a neutrophil is a leukocyte that stains easily
with neutral dyes; when bone marrow is depressed, decreased WBC count
(leukocytopenia), decreased RBC count (anemia), and decreased platelet
count (thrombocytopenia) have occurred.
Nursing implications: Arrange for blood and urine tests to evaluate renal function before
therapy and weekly during therapy; monitor liver function tests and CBC;
reduce or discontinue if renal toxicity occurs (proteinuria, elevated BUN,
plasma creatine, serum electrolytes); use special caution when handling
cytotoxic agents; contact with skin poses a carcinogenic hazard to the area
exposed; wear rubber gloves; if powder or solution comes into
contact with the skin, wash immediately with soap and water; arrange for
pretherapy with an antiemetic if needed to decrease the severity of
nausea and vomiting; monitor urine output frequently for any signs of renal
failure.
Anticancer Drugs ◆ 147
HORMONES AND HORMONE ANTAGONISTS
1. The hormones and hormone antagonists are the least toxic of all anticancer drugs.Because these agents act through specific hormone receptors on target tissue, theireffects are relatively selective. As a result, these drugs are generally devoid ofthe severe toxicities that characterize most anticancer agents.
2. The hormonal anticancer drugs fall into five basic categories: (1) androgens andantiandrogens, (2) estrogens and antiestrogens, (3) progestins, (4) gonadotropin-releasing hormone (GnRH) analogues, and (5) glucocorticoids.
3. The principal indications for these drugs are cancer of the breast, endometrium,and prostate.
4. The glucocorticoids are also used against lymphomas and certain leukemias.
◆ Anticancer Drugs: Hormones and Hormone Antagonists
Generic Name Trade Name Indications
Androgens
Fluoxymesterone Halotestin Breast cancer
Testosterone No commonly used
trade name
Breast cancer
Antiandrogens
Flutamide Eulexin Metastatic prostate cancer
Estrogens
Diethylstilbestrol • Stilphostrol Prostate and breast cancer
Ethinyl estradiol • Estinyl Prostate and breast cancer
Estrogen mustards
Estramustine • Emcyt Prostate cancer
Tamoxifen Nolvadex Breast cancer
Progestin
Medroxyprogesterone Depo-Provera Endometrial cancer
GnRH analogues
Goserelin Zoladex Prostate cancer
Glucocorticoid
Prednisone Deltasone Acute and chronic lymphocytic leukemias,
Hodgkin’s and non-Hodgkin’s lymphomas
Major side effects: Antiandrogen: gynecomania (abnormal sex drive
in the male); toxic hepatitis has occurred that
has been fatal to patients.
Estrogen: fluid retention, hypercalcemia, depression,
thromboembolic disorders; gynecomastia may
occur in males.
148 ◆ Chapter 13
◆ Anticancer Drugs: Hormones and HormoneAntagonists (continued)
Generic Name Trade Name Indications
Major side effects:
(continued)
Estrogen mustard: thrombosis resulting in myocardial
infarction (MI) or stroke, fluid retention,
hypercalcemia
Antiestrogen: Nausea, vomiting, hot flashes,
menstrual irregularities
Progestins: fluid retention and hypercalcemia;
progestins are teratogens and should be avoided in
the first 4 months of pregnancy.
Gonadotropin-releasing hormone analogues: bone
pain and urinary obstruction
Glucocorticoids: adrenal insufficiency, increased
susceptibility to infection, peptic ulcers, fluid and
electrolyte disturbances, osteoporosis, growth
retardation in children
Note: Side effects of androgens include clitoral enlargement, proliferation of facial and body hair, deepening of the voice, and
increased libido.
BIOLOGICAL RESPONSE MODIFIERS
1. Biologic response modifiers are drugs that alter responses to cancer.
2. Many of these drugs are immunostimulants that enhance host defenses againstcancer.
3. Some of these drugs render cancer cells nonmalignant by causing them to dif-ferentiate into nonproliferative forms. Some enable the host to better tolerate themyelosuppressive actions of anticancer drugs.
◆ Anticancer Drugs: Biologic Response Modifiers
Generic Name Trade Name Indications
Androgens
Interferon alfa-2a Roferon- A Hairy cell leukemia
Interferon alfa-2b Intron A Kaposi’s sarcoma
Aldesleukin Proleukin Metastatic renal cancer
Interleukin-2
Levamisole Ergamisol Stage II colon cancer (combination
therapy with fluorouracil)
(continued)
Anticancer Drugs ◆ 149
◆ Anticancer Drugs: Biologic Response Modifiers (continued)
Colony-stimulating factor
Generic Name Trade Name
Filgrastim NeupogenDesired effects: Increase the production of neutrophils (white blood cells) within the bone
marrow
Therapeutic actions: Human granulocyte colony-stimulating factor is produced by recombinant DNA
technology; increases the production of neutrophils within the bone marrow
with little effect on the production of other hematopoietic cells
Treatment: Decreases the incidence of infection in patients with neutrophils (leukocytes that
stain easily with dye); malignancies in patients receiving myelosuppressive
anticancer drugs are associated with a significant incidence of severe
neutropenia with fever; Neupogen helps reduce the duration of neutropenia
following bone marrow transplant.
Major side effects: Headache, fever, generalized weakness, fatigue, alopecia (absence or loss of
hair, especially on the head), rash, mucositis (inflammation of mucous
membranes), nausea, vomiting, anorexia, diarrhea, constipation, bone pain.
Nursing implications: Obtain CBC and platelet count prior to and twice weekly during therapy; doses
may be increased after chemotherapy cycles according to the duration and
severity of bone marrow suppression; do not give within 24 hours before or
after chemotherapy; give daily for up to 2 weeks until the neutrophil count is
10,000/mm3; discontinue therapy if this number is exceeded; store drug in
refrigerator; do not shake vial; each vial can be used only once; do not reuse
syringes or needles (a proper container for disposal will be provided); for
home situations, another person should be instructed in the proper
administration technique; use sterile technique; Neupogen can be
administered IV or SC.
Chapter
14ImmunosuppressiveDrugs
IMMUNOSUPPRESSIVE DRUGS
1. Immunosuppressive drugs inhibit immune responses.
2. These agents have two principal applications: (1) prevention of organ rejection(e.g., liver transplant) or suppression of allograft rejection (transplant of skin fromthe same species), and (2) treatment of autoimmune disorders (e.g., systemic lupuserythematosus, rheumatoid arthritis).
3. Two toxicities are of particular concern when immunosuppressive drugs are ad-ministered: increased risk of infection and increased risk of neoplasms.
4. Cyclosporine (Sandimmune) is the most effective immunosuppressant available,and is the drug of choice for preventing organ rejection.
5. Oral administration is preferred; intravenous administration is reserved for clientswho cannot take the drug orally.
6. Cyclosporine increases the risk of infection, although less than the cytotoxic im-munosuppressants.
150
Immunosuppressive Drugs ◆ 151
◆ Immunosuppressive Drugs
Generic Name Trade Name
Helper T cell depressant
Cyclosporine SandimmuneGlucocorticoids
Methylprednisolone
sodium succinate
Solu-Medrol, Medrol
Prednisone • Apo-Prednisone
Hydrocortisone Cortef, HydrocortoneDexamethasone DecadronCortisone acetate Cortone AcetateFludrocortisone Florinef AcetateCytotoxic drugs
Cyclophosphamide CytoxanMethotrexate • Amethopterin
Antibodies
Antithymocyte globulin,
equine
No commonly used trade name
Rho(D) immune globulin RhoGAMTreatment: Prevention of organ transplant rejection; treatment of
autoimmune disorders
Side effects: Cyclosporine: nephrotoxicity, infection, hypertension
Glucocorticoids: depression, euphoria, hypertension, decreased
wound healing, adrenal suppression
Cytotoxic drugs: bone marrow depression (myelosuppression)
Antibodies: reactions are uncommon and mild
Chapter
15Drug Therapy forOsteoporosis
Osteoporosis is a metabolic bone disorder in which the rate of bone resorption acceler-ates while the rate of bone formation slows down, causing a loss of bone mass. Bonesaffected by this disease lose calcium and phosphate salts and thus become porous, brit-tle, and abnormally vulnerable to fracture. Osteoporosis may be primary or secondaryto an underlying disease. Primary osteoporosis is often called senile or postmenopausalosteoporosis because it most commonly develops in elderly postmenopausal women.
◆ Bisphosphonates (Calcium Regulators)
Generic Name Trade Name
Alendronate sodium FosamaxEtidronate disodium Didronel, Didronel IVZoledronic acid ZometaPamidronate disodium ArediaRisedronate sodium ActonelDesired effects: Bisphosphonates inhibit bone resorption by inhibiting osteoclast activity
and promoting osteoclast cell apoptosis (disintegration of cells into
membrane-bound particles that are then phagocytosed by other cells);
this action leads to decreased release of calcium from bone and
decreased serum calcium level
(continued)
152
Drug Therapy for Osteoporosis ◆ 153
◆ Bisphosphonates (Calcium Regulators) (continued)
Generic Name Trade Name
Risedronate (continued) Actonel (continued)
Side effects: Fosamax: headache, dizziness, hypertension, chest pain, nausea,
diarrhea, altered taste, metallic taste, abdominal pain, anorexia,
esophageal erosion, elevated BUN and serum creatinine,
hypokalemia, hypocalcemia, dyspnea, coughing, pleural effusions,
increased or recurrent bone pain
Treatment: Bisphosphonates are used for treatment of osteoporosis (oral) in
postmenopausal females and in males; hypercalcemic malignant tumors
in patients who cannot be adequately managed by diet or oral
hydration (parenteral); Paget’s disease of bone (oral)
Nursing implications: Administer Fosamax with a full glass of water 2 hours before meals or any
other medication; make sure the patient stays upright for at least 30
minutes after administration; make sure that all patients taking
bisphosphonates are well hydrated before and during therapy with
parenteral agents; monitor serum calcium levels before, during, and
after therapy; ensure adequate vitamin D and calcium intake; provide
comfort measures if bone pain returns.
Contraindications and
cautions:
Allergy to bisphosphonates, hypocalcemia, pregnancy, lactation, severe
renal impairment; use cautiously in the presence of renal dysfunction
or upper GI disease
◆ Estrogen Receptor Modulator
Generic Name Trade Name
Raloxifene HCl EvistaDesired effects: Evista increases bone mineral density without stimulating the endometrium
in women and modulates the effects of endogenous estrogen at
specific receptor sites.
Side effects: Depression, lightheadedness, dizziness, headache, corneal opacities,
decreased visual acuity, retinopathy, venous thromboembolism, severe
itching of external female genitalia, vaginal bleeding, vaginal discharge,
peripheral edema
Treatment: Prevention and treatment of osteoporosis in postmenopausal women
Nursing implications: Administer daily without regard to food and arrange for periodic blood
counts during therapy; monitor patients for possible long-term effects,
including cancers and thromboses associated with other drugs in this
class; counsel patients about the need to use contraceptive measures
to avoid pregnancy while taking this drug; inform patients that serious
fetal harm could occur; assess patients for history of allergy to Evista,
pregnancy, lactation, smoking, venous thrombosis
154 ◆ Chapter 15
◆ Hormonal Agent
Generic Name Trade Name
Calcitonin (human),
calcitonin (salmon)
Calcimar, Cibacalcin, Miacalcin Nasal Spray
Desired effects: The calcitonins are polypeptide hormones secreted by the
thyroid; human calcitonin is a synthetic product classified as
an orphan drug; salmon calcitonin appears to be a
chemically identical polypeptide, but with greater potency
per milligram and longer duration; both inhibit bone
resorption, lower elevated serum calcium, and increase the
excretion of filtered phosphate, calcium, and sodium by the
kidney.
Treatment: Postmenopausal osteoporosis in conjunction with adequate
calcium and vitamin D intake to prevent loss of bone mass
(salmon calcitonin); emergency treatment for hypercalcemia
(salmon calcitonin); Paget’s disease (human and salmon
calcitonin); Paget’s disease is characterized by excessive
bone resorption followed by abnormal bone formation.
Side effects: Salmon calcitonin: local inflammatory reactions at injection site
and nasal irritation (nasal spray); human calcitonin: urinary
frequency
NURSING IMPLICATIONS
1. These drugs can be given SC or IM; the patient or a significant other must learnhow to do this at home. Refrigerate the drug vials. For intranasal use, alternatenostrils daily; notify health care provider if significant nasal irritation occurs.
2. Give skin test to patients with any history of allergies; salmon calcitonin is aprotein, and risk of allergy is significant.
3. Refrigerate nasal spray until activated, then store at room temperature.
4. Use reconstituted human calcitonin within 6 hours.
5. Maintain parenteral calcium on standby in case of development of hypocalcemictetany.
6. Monitor serum alkaline phosphatase and urinary hydroxyproline excretion priorto therapy and during the first 3 months, then every 3–6 months during long-termtherapy.
7. Salmon calcitonin is contraindicated with allergy to salmon calcitonin or fish prod-ucts, and during lactation. Use cautiously with renal insufficiency, osteoporosis,or pernicious anemia.
Drug Therapy for Osteoporosis ◆ 155
DRUGS FOR BENIGN PROSTATIC HYPERPLASIA
◆ Alpha-Adrenergic Blockers
Generic Name Trade Name
Tamsulosin FlomaxPrazosin MinipressTerazosin HytrinDoxazosin mesylate CarduraDesired effects: Alpha-adrenergic blockers relieve symptoms of benign prostatic hyperplasia
(BPH) and decrease blood pressure in patients with hypertension.
Side effects: Headache, fatigue, dizziness, lethargy, vertigo, rhinitis, asthenia, anxiety,
paresthesias, increased sweating, muscle cramps, insomnia, eye pain,
conjunctivitis, tachycardia, palpitations, edema, orthostatic hypotension, chest
pain, sexual dysfunction, increased urinary frequency
Nursing implications: Monitor for orthostatic hypotension, which is most marked in the morning and is
accentuated by hot weather and alcohol; sodium and water retention,
increased plasma volume, edema, dyspnea, syncope
Clinical alert: Name confusion has occurred between Fosamax (alendronate) and Flomax
(tamsulosin); use caution
◆ Androgen Hormone Inhibitors
Generic Name Trade Name
Finasteride Propecia, ProscarDoxazosin mesylate CarduraDesired effect: These relieve symptoms of benign prostatic hyperplasia (BPH).
Side effects: GI distress, impotence, decreased libido, decreased volume of ejaculation
Treatment: Proscar and Cardura are used for the treatment for symptomatic benign prostatic
hyperplasia (BPH); most effective with long-term use; reduce the need for
prostate surgery
Nursing implications: Administer Proscar and Cardura without regard to meals; protect container from
light; arrange for regular follow-up, including prostate exam, PSA levels,
evaluation of urine flow and liver and kidney function; monitor urine flow and
output; an increase in urine flow may not occur; do not allow pregnant
women to handle crushed or broken tablets because of risk of inadvertent
absorption, adversely affecting the fetus; alert patients that libido may be
decreased as well as the volume of ejaculate; these effects are usually
reversible when the drug is stopped.
Chapter
16Drugs Used to TreatPoisoning
MANAGEMENT OF POISONING
1. Poisoning is defined as a pathologic state caused by a toxic agent.
2. Sources of poisoning include medications, plants, drug abuse, and environmentalpollutants.
3. These toxicants may enter the body orally, by inhalation, and by absorption throughthe skin.
4. Poisoning may be accidental or intentional.
5. Poisoning occurs at an estimated rate of 5 million per year, and about 6000 deathsresult.
6. Approximately 60% of these fatalities are due to ingestion of drugs, either pre-scription medicines or over-the-counter preparations. The remaining deaths arecaused by other chemicals.
7. The incidence of poisoning is highest in young children; however, the mortalityrate in this group is low.
8. Most poisoning-related hospital admissions result from suicide attempts by adults.
156
Drugs Used to Treat Poisoning ◆ 157
9. In the United States there are more than 500 local poison control centers and over50 certified regional centers. All of these centers are accessible by phone and canprovide immediate instructions on the management of acute poisoning. In the ma-jority of cases, the information supplied will permit successful treatment at home.By facilitating rapid treatment, poison control centers can decrease morbidity andmortality and can help reduce the cost of emergency care.
10. Management of poisoning is a medical emergency and requires rapid treatment.Management has five basic elements: (1) supportive care, (2) identification of thepoison, (3) prevention of further absorption, (4) promotion of poison removal, and(5) use of specific antidotes.
11. Supportive care is based on the patient’s clinical status and includes maintenanceof respiration and circulation.
12. Careful evaluation of the individual who has been affected by a toxic substance isessential to determine by which route the poison should be removed or eliminated,if necessary.
13. The route of removal is determined by the toxic agent causing the poisoning.Removal can be attempted in several ways: (1) by directly removing it fromthe stomach, if the poisoning is discovered early; (2) by increasing the rate oftransit of poison through the intestines (this may not be effective, as absorptionoccurs as it moves through the intestines); or (3) if the toxic agent has alreadybeen assimilated into the system by injection or late discovery, it is directly re-moved from the bloodstream using hemoperfusion or peritoneal dialysis. Con-tact poisons may be flushed from skin and eyes with copious amounts of plainwater.
DRUGS USED TO MINIMIZE ABSORPTION OF POISONS
1. The American Academy of Pediatrics recommends that Ipecac syrup shouldonly be administered on the advice of a Poison Control Center or physician,especially in the case of infants and children. This also applies to adults be-cause there are many situations where emesis is contraindicated including poi-soning involving strong acids or alkalies, kerosene, gasoline, unconscious, semi-comatose, ingestions of sharp objects (e.g., glass, nails) or severely inebriated,patients experiencing convulsions, or patients who have ingested petroleumdistillates.
The use of ipecac syrup in patients who have ingested petroleum is controversial.Use may be considered in poisoning involving petroleum distillates when theproduct contains a more toxic ingredient such as heavy metals pesticides; mixedpoisonings where the quantity ingested is certain to be toxic.
a. Ipecac syrup is available without a prescription in 1 oz. (30 mL) bottles bearingthe following instructions. For emergency use to cause vomiting in poisoning.Before using, call physician, poison control center, or hospital emergencyroom immediately for advice.
158 ◆ Chapter 16
b. Gastric lavage, a nasogastric tube, is put into the stomach and several litersof half-strength saline solution may be used to lavage the stomach. The newLavacuator tube may also be used. This procedure is repeated until lavage returnflows clear.
2. Cathartic and enemas may be used to increase the rate of transit of toxin throughthe intestines. Saline cathartics (e.g., sodium, magnesium sulfate) are the agentsof choice.
3. Activated charcoal may be used following emesis or lavage. The activated charcoalmay be instilled or swallowed to act as an absorbent.
a. Activated charcoal should be given as soon after poison ingestion as possible.
b. Activated charcoal is used as an adjunct in the treatment of oral poisoning withheavy metals, mercuric chloride, strychnine, atropine, mushrooms, aspirin, andmost drugs.
c. Activated charcoal is not effective for poisoning with cyanide, DDT, ethanol,methanol, caustic alkalis, ferrous sulfate, boric acid, organophosphates, andcarbonate.
4. Drugs that enhance renal excretion alter the pH of the urine; this accelerates theexcretion of organic acids and bases. An agent that lowers urine pH is ammoniumchloride. It renders the urine more acid, decreases the passive reabsorption of thebase (e.g., amphetamines, phencyclidine), and thereby enhances their excretion.An agent that increases urine pH is sodium bicarbonate. It renders the urine morealkaline, decreases the passive absorption of acids (e.g., aspirin, phenobarbital),and thereby enhances their excretion. Because of the buffer system present in theblood, sodium bicarbonate and ammonium chloride have relatively little effect onthe pH of the blood.
NONDRUG METHODS OF POISON REMOVAL
1. There are several nondrug procedures for removal of toxin from the blood:hemodialysis, hemoperfusion, and exchange transfusion.
2. Peritoneal dialysis has two advantages: the procedure is relatively simple to per-form, and it is considered more effective than other procedures. As a result, its usein the management of acute poisoning is increasing.
3. Hemoperfusion is a process in which blood is removed from the body, passed overa column of charcoal or absorbing resin, and then reinfused into the body. If theaffinity of the resin for a particular poison is sufficiently high, this procedure canstrip a toxin from its binding sites on plasma protein. The principal disadvantageof hemoperfusion is loss of platelets.
SPECIFIC ANTIDOTES USED FOR HEAVY METAL POISONING
1. The heavy metals most frequently responsible for poisoning are lead, iron, mercury,arsenic, gold, and copper.
Drugs Used to Treat Poisoning ◆ 159
2. Useful chelating agents have a high affinity for heavy metals and therefore competesuccessfully with endogenous molecules for metal binding.
OTHER IMPORTANT ANTIDOTES
Throughout this text we have considered the toxic effect of various drugs. When appro-priate, we have discussed specific antidotes used to treat these toxicities. For example,when discussing the adverse effects of opioids, we also discussed treatment of opioidsoverdosage with naloxone (Narcan). Similarly, when we discussed heparin toxicity, wediscussed the use of protamine sulfate as treatment.
◆ Heavy Metal Antagonists
Generic Name Trade Name Specific Metal
Deferoxamine Desferal Iron
Dimercaprol Bal in Oil Gold
Edetate calcium disodium Calcium EDTA Lead
Penicillamine • Depen Mercury, lead, copper, iron
Succimer Chemet Lead, mercury, arsenic
The major specific antidotes presented in previous chapters are listed below.
◆ Specific Antidotes
Toxic/ Substances Overdosed
Generic Name Trade Name Chapter
Naloxone Narcan Opioids (e.g., morphine) 3
Phytonadione (Vitamin K) AquaMEPHYTON Coumadin 4
Protamine sulfate No trade name Heparin 4
Glucagon No trade name Insulin 7