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Pharmacologic in the Geriatric Population 1
Pharmacologic in the Geriatric Population
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Do you have a Pharm Dictionary?
• www.nlm.nih.gov/medlineplus/mplusdictionary.html
Issues for the Geriatric Population
• Pattern of drug use • Altered response to drug therapy• Multiple disease states• Lack of proper drug testing• Problems with drug education and
compliance (Health Literacy)• Financial issues impacting medication usage
Other Factors in Geriatric Drug Use
• Presence of Multiple Chronic Conditions o 80% of those 65+ have multiple diseases with
medications
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Comorbidities More drugs
Increase risk of drug-drug interactions
Commonly prescribed meds related to ED admissions among elderly
• From 2007 to 2009, 99,628 “emergency” hospitalizations of patients > 65 years of age occurred due to adverse drug eventso 66% being attributed to unintentional drug overdoseo 48% of the hospitalizations involving those > 80 years
of age • 4 drugs were implicated in 67% of patients
o Warfarin (33.3%)o Insulin (13.9%)o Anti-platelet agents (13.3%)o Oral hypoglycemic agents (10.7%)
Altered Response to Drugs
• Pharmacokinetic Changes in the Body (The way in which one drug moves throughout the body)o Absorptiono Metabolismo Distributiono Excretion
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Pharmacokinetic change
• Absorptiono Altered GI function in elderly due to
Decrease gastric acid Decrease stomach emptying Decrease absorption area Decrease motility Sometimes decreased H2O intake
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Pharmacokinetic change
• Metabolismo The process to inactivate drugs and create
water-soluble by-products (metabolites) that can be excreted by the kidneys.
o Primarily takes place at liver• Interference with metabolism
oMAO inhibitors (e.g. Selegiline) have lots of contraindications and drug interactions
o Vitamin K with Coumadino Vitamin B with Levodopa9
Pharmacokinetic change
• Hepatic Metabolism o Decrease liver masso Decrease liver blood flowo Decrease enzyme activity
Leads to decreased liver metabolism
o Injury to liver (trauma, CA, ETOH also impact the liver metabolism)
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Pharmacokinetic change
• Distributiono Decrease in body water contento Increase in body fato Decrease in lean body masso Decrease in plasma proteins
e.g. aspirin or warfarin may produce a greater response because there will be less drug bound to
o Drugs are area specific - either bind to receptors or act on tissues in order to be effective, e.g. water-soluble, fat soluble, protein affinity
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Pharmacokinetic change
• Excretiono Primarily takes place at kidneyo Kidney filters the drug from the circulation and
excrete it from the body via the urineoDecreased Renal functioning with age
Decrease kidney mass Decrease renal blood flow Decrease in tubular function in the nephron
oResults in? Build up/Accumulation of drug12
Pharmacodynamic Interactions
• The way in which one drug’s action interferes with the action of the other
• Pharmacologic antagonism• Physiologic antagonism• Synergism
Pharmacodynamic Changes
Pharmacodynamic Changes
• Systemic drug response altered due to physiological changes in the elderly
• Each patient is different in his response to medications
• Altered response may occur with alterations in drug-receptor attraction which can increase or decrease sensitivity
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Pharmacodynamic Changes
• There are changes in receptor linkage or coupling to the cell that occurs in certain tissues as a function of aging.
• In some patients the biological response of a medication may be blunted due to changes in cellular structure and function that occur in the elderly.
• ½ life longer with aging adult
OTC drug use in Geriatrics
• >60 y.o. 40% use OTC every day• Used for pain (OA), digestive purposes
(laxative), decongestants (sometimes alcohol based)
• 80% take with alcohol, Rx drugs or both • Use of alternative meds and treatment
o can alter PT/PTT times, absorption
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Psychotropic Drugs
• Sedative Hypnotic?
• Antianxiety Agents?
• Antidepressant Meds?
• Antipsychotic Medso Haloperidol (Haldol)
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Sedative Hypnotics
• Benzodiazepineo Primary drugs used to promote sleep and
decrease anxiety in older adultso Increase central inhibitory effect of GABAo Temazepam (Restoril)o Side effects
“hangover”, drowsiness and sluggish, anterograde amnesia (short-term memory for the period immediately preceding drug administration, rebound insomnia
Anti-Anxiety Meds
• Decrease agitation• Drugs directly stimulating serotonin receptors
in certain parts of the brain (dorsal raphe nucleus)
• Benzodiazepine o Diazepam (Valium)o Lorezepam (Ativan)
• Azapironeso Buspirone (BuSpar)=“Busy” drug decreases to help
anxiety20
Antidepressant
• Increase synaptic transmission in CNS pathways that utilize norepinephrine, dopamine, or serotonin=same pathway
• Tricyclico Amitriptyline (Elavil)=“elevate your mood”o Produce anticholinergic (Ach) effects
dry mouth, constipation, urinary retention, and CNS symptoms such as confusion, cognitive impairment, and delirium. (frontal lobe)
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Antidepressant
• MAO inhibitorso Isocarboxazid (Marplan)o Causes orthostatic hypotension, insomnia.
• 2nd generation (SSRI)o Bupropion (Wellbutrin)o Fluoxetine (Prozac)o Causes GI irritation and bleeding o May take anywhere from 1 to 6 weeks to take effect22
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Sinemet (Carbidopa/Levodopa)
Effective for mild to moderate Parkinson’sNot effective for end stage.
• GI problems o Nausea, vomiting
• Cardiovascular problems o Arrythmia, orthostasis
• Neuropsychiatric problems o Confusion, depression, anxiety, hallucination
• On and OFF phenomenon• End of dose akinesia24
FDA Warning about Stalevo (Carbidopa + Levodopa + Entacapone)
• [Posted 08/20/2010] Issue: FDA notified healthcare professionals that it is evaluating clinical trial data that suggest patients taking Stalevo (a combination of carbidopa/levodopa and entacapone) may be at an increased risk for cardiovascular events (heart attack, stroke, and cardiovascular death) compared to those taking carbidopa/levodopa (sold as the combination product, Sinemet). http://www.nlm.nih.gov/medlineplus/druginfo/meds/a601068.html
Sinemet (Carbidopa/Levodopa) formulation
• Coordinate patient care time at the peak effects of drugCarbidopa/Levodopa Time-to-peak
concentration Effective Duration
Immediate Release10/100, 25/100, 25/250Usually 3 or 4 times a day
30 min 2-4 hr
Controlled Release (CR)25/100, 50/200Usually 2 or 4 times a day
2 hours 4-6 hr
Parcopa (orally disintegrating tablet) 10/100, 25/100, 25/250Usually 3 or 4 times a day
30 min 1/2-1 hr
Sinemet (Carbidopa/Levodopa)
• The peak concentrations of levodopa after a single dose of Sinemet CR 50/200 increased by 25% when administered with food.
• Vitamin B 6 can reduce the effects of levodopa when levodopa is taken by itself.
• Large amounts of Vitamin B 6 are also contained in some foods, such as bananas, egg yolks, lima beans, meats, peanuts, and whole grain cereals. Patient should limit the amount of these goods while on Sinemet.
Pain and inflammation medications
• Opiod Analgesics (aka Narcotics)oMorphine, Demoral, CodeineoChanges the pain perception but not painful
stimuluso ADR: sedation, mood changes, nausea,
vomiting, constipation, orthostatic hypotension, respiratory depression, drug addiction
Administration of morphine in the periaqueductal gray and serotonin (5-HT) in the Raphe nucleus produces analgesia.Fig 8.3B. neuroscience.uth.tmc.edu/s2/chapter08. html
Pain and inflammation medications
• NSAIDso Anagelsic, decrease inflammation and fever,
anticoagulanto ADR: GI bleeding, renal and liver problems,
impair bone healing• Acetaminophen
o Analgesic, decrease fevero ADR: more toxic to liver than NSAIDs
• NSAIDS and Acetaminophen inhibit the synthesis of prostaglandins at different sites.
Peripheral sensitization after an injury
Fig 5.2 Harrison's Neurology in Clinical Medicine, 2010
Pain and inflammation medications
• COX-2 inhibitor (Celebrex)o Inhibit the production of harmful
prostaglandinso ADR: GI problems, cardiovascular problems
such as MI and stroke (therefore VIOXX was removed from the market)
Pain and inflammation medications
• Glucocorticoidso Anti-inflammatory (suppressing leukocyte and
inhibit proinflammatory substances such as cytokines and prostaglandins)
o ADR: HTN, peptic ulcer, aggravating DM, glaucoma, increased risk of infection, inhibit corticosteroids production by adrenal cortex
oGlucocorticoids produce a general catabolic=destroyer effect throughout the body, breaking down bones, ligaments, tendons, skin and muscles
Cardiac Meds
• Table 4-5
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Drugs in geriatric hypertension
• Current normal BP thresholds o Systolic/Diastolic BP < 140/90 mmHg in older adultso Systolic/Diastolic BP < 130/80 mmHg in older adults
with comorbidities, e.g chronic renal insufficiency or diabetes mellitus
o Hypertension T(x) Meds: B-blockers, Diuretics,
β-blockers, α-blockers (sympatholytic agents)
• Reduce excessive sympathetic stimulation of the heart and peripheral vessels to decrease HR and myocardial contraction forceo blocking epinephrine & norepinepherine
• Indications of β-blockers:o HTN: Atenolol (Tenormin)o Angina: Metoprolol (Lopressor)o Arrthmias: Nadolol (Corgard)o CHF
• β-blockers cause hypotension, dizziness, syncope36
Diuretics
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Act on kidneys to increase the excretion of H2O sodium
Decrease the volume of fluid and thus cardiac workload
Volume depletion can lead to hyponatremia & hypokalemia
Diuretics
• Indications: CHF, Hypertension, edema• Loop diuretic: Furosemide (Lasix)• Thiazide diuretic: Chlorothiazide (Diruil)• Potassium sparing diuretic: Spironolactone
(Aldactone)• ADR: confusion, weakness, fatigue, increase
urinary output (annoying side effects)• Common drug regimen
o Diuretics + β-blockero Diuretics + ACE inhibitor38
Angina pectoris (chest pain – a symptom of coronary artery disease)
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Angina occurs when Myocardial O2 demand> Myocardial O2 supply
Nitrates cause vasodilation of the peripheral vasculature
Decreases Cardiac Preload (the amount of blood returning to the heart)
Decrease cardiac Afterload (the pressure in the vasculature)
Temporarily reduce cardiac workload and O2 demand
Organic Nitrates
• Indications of organic nitrateso Angina pectoris: Nitroglycerin (nitrostat)
• Sublingual or transdermal by a patch• ADR: decreased BP, orthostatic hypotension,
dizziness
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ACE Inhibitors (angiotensin-converting enzyme)
• Block the conversion of Angiotensin 1 to Angiotensin 2 (a vasoconstrictor) and thus decrease the pressure in peripheral vasculature the heart pump against
• Indicationso HTN: Captopril (Capoten)o CHF: Enalapril (Vasotec)
• ADR: hypotension, orthostatic hypotension• Common drug regimen
o ACE inhibitor + Calcium blocker 41
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Anti-Arrhythmic Medications
• Sodium Channel Blockerso Lidocaine (Xylocaine)o Stabilize opening/closing membrane Na2+ channels
to control myocardial excitability
• β-Blockers o Nadolol (Corgard)o Prolong the duration of cardiac repolarization
• Calcium Channel Blockerso Diltiazem (Cardizem)o Decrease myocardial excitability by limiting entry of
Ca2+ into cardiac muscles
Pattern of Drug Use in the Elderly
• PolypharmacyoDrug regime of a patient contains one or more
“unnecessary” medications (both OTC and Rx meds)
• Administration of drugs to treat an illness creates an adverse reaction, drug side effects seen as new symptoms. Therefore, more drugs are administered.
Characteristics of Polypharmacy
• Use medication for no apparent reason
• Use of duplicate medications
• Use of concurrent interacting medications
• Use of contraindicated medications
• Use of inappropriate drugs
• Use of drug therapy to treat adverse drug reactions
• Patient improves when meds are discontinued
Prevention of Polypharmacy
• Drug regime reviewed periodicallyoWritten list, One pharmacy, Primary Care
Physician
• Unnecessary or harmful drugs are discontinuedoHave family member discard expired drugs
• New drugs added only if truly needed
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Prevention of Polypharmacy
• Communication between various physicians
• PT’s can assist by recognizing changes in patient’s response to drugso Identify changes as drug reactions rather than
new symptomsoHave patient bring a list to therapy oChart review
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Common Adverse Drug Reactions (ADR)
• GI problemsomust adjust dose and type of medication to
minimize problems
• Sedationomany drugs will increase sedative properties
in the elderly
• Confusionomay increase in patients already confused
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Other adverse drug reactions
• Depression • Orthostatic Hypotension • Fatigue and Weakness• Dizziness and Falls• Extrapyramidal symptoms (dyskinesia)• Anticholinergic Effects
o CNS effects with confusion, nervousness, drowsiness, dizziness
o Dry mouth, constipation, urinary retention, tachycardia, blurred vision
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Lack of Proper Drug Testing in the Geriatric Population
• Evaluation of drugs in geriatric patients may not have occurred prior to FDA approval
• In 1997, FDA established the Geriatric Use Subsection to provide guidance for labelingoHealthy People 2010: polypharmacy as a part
of the safety issues (2020 as well)
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Societal Issues with Geriatric pharmacy
• Somewhat recent ventureo Falls & behavioral changes were considered
normal • Currently FDA only requires safety &
efficacy for the target area of the drug for those 20-60 y.o.
• The impact on advertisingo Just because it is FDA approved and on TV, is
it safe and effective?51
Compliance issues
1. Number of medications 2. Inadequate information or instructions3. Cultural background4. Social isolation5. Duration of drug treatment6. Cost 7. Limitations of illness (physical & mental)
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Patient education and self-adherence to drug therapy issues
• Many drugs are over prescribed and misused in older adults
• Drugs aren’t always taken as directed
• Decline in cognitive function, poor eyesight
• Drug Costs
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Physical Therapy Implications
• Distinguishing Drug effects from Symptoms
• Scheduling Physical Therapy Sessions around Dosage Schedule
• Promote a synergistic relationship between drugs and physical therapy interventions
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Physical Therapy Implications
• Avoid harmful interactions between PT procedures and Drug Effects
• Improving Education and Compliance with Drug Therapy in the Elderly
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