Gimme ‘da DRUGS, man!

Pharmacology

During the transport of an ACS patient, you notice that after giving nitroglycerin, their blood pressure drops to s*&#! (S*&#! = 50/palp). As you wonder “how did nitroglycerin drop it that low” you give a fluid bolus but also grab the Dopamine. “How does Dopamine work? How do I give it? What are the side effects?” You ponder, noticing a bit late that your patient has been unconscious for the past 10 seconds, in V-fib. Things just went from S*&#! to F*&#!...

Case

Generic Name/Trade Name: different names depending on who is making it. Examples: acetaminophen/Tylenol, fentanyl/Sublimaze, hydromorphone/Dilaudid.

Mechanism of Action: how it works in the bodyPharmacokinetics – how it is absorbed, distributed,

and eliminated from the bodyDosage/Route – how much and where (oral, rectal,

nasal, IV, IM, subcutaneous)Indications/Contraindications – what its used for, what

will prevent you from giving it.Adverse effects – things that might go wrong if you

give it

Pharmacology Terms

Therapeutic levels – range of serum levels in which drug will have its predicted value

LD50 – level at which drug will kill 50% of the patients given the drug

Metabolism – how the body transforms the drug to make it inert and ready for removal

Excretion – how the drug exits the bodyLiver/fecalKidney/urineCombination

Drug Metabolism

Right DrugRight Patient

Think Mass Casualty situationsRight Dose

Have a reference handyRight TimeRight RouteRight Documentation

Time, who gave it, what happened!!

The Six Rights

ReceptorA protein made by the cell, nestled in the cell

wall that acts as a signal sentinel.Acts in response to this signal in a certain way

Usually by a second messenger systemThe structure of the receptor is such that it

can be stimulated, overstimulated, or blocked from acting.

The second messengers cause the production of enzymes

How does a drug work?

Stimulate a receptor epinephrine, dopamine, Narcotics, Benzos, succinylcholine,

albuterolBlock a receptor

lidocaine, aspirin, Narcan, Vecuronium, atropine, adenosine, amiodarone, diphenhydramine

Directly effect body chemistry/osmolarity electrolytes, bicarb, NaCl, mannitol

Act as an enzyme or catalyst tPA, thiamine, cyanocobalamin

Block an enzymeAct as substrate for a chemical reaction

Mucomyst, nitroglycerin, oxygen, glucoseKill Bugs - antibiotics

How does a drug work?

Sympathetic Alpha (1, 2)

Constricts blood vessels, dilates pupilsBeta

1 – increases heart rate2 – dilates bronchioles, arterioles

ParasympatheticMuscarinic

Relaxes smooth muscle (except bronchioles)Decreases heart rate, electrical conductionConstricts pupils

Autonomic Nervous System

GABACauses a decrease in neuronal activity

OpioidBlock pain reception in the spinal cordCauses euphoria (mu receptor)

AcetylcholineAllows for transmission of nerve impulse to a

muscle group – contracts muscleDopamine

Poorly understood, neuronal signaling and cognition

Other Nervous System Receptors

Aspirin (Ecotrin, Bayer)Action: Thromboxane A2 inhibitor, causes

platelet function inhibitionDosage: 324mg oral chewedIndications: Cardiac chest painContraindications: Allergy, GI bleedingSide Effects – bleeding, GI upset

The EMT formulary

Nitroglycerin (EMT can assist patient with his/her own, AEMT and medic can give without prior Rx)Effect: vasodilator, chest pain relieverDosage: 0.4mg sublingual Q 15 min x3Indications: chest painContraindications: hypotension, allergySide Effects: Headache, hypotension, syncope,

cardiac arrest

EMT Formulary

Albuterol (Proventil)Effect: Dilates smooth muscle in bronchioles

(B2)Dosage: 1-2 puffs per MDI PRN (max three

doses); AEMTs and Medics – 1 ampule neb prn, max 3

Indications: Asthma or COPD exacerbationsContraindications: noneSide Effects: jitteriness, tachycardia,

arrhythmia, sweating, anxiety

EMT formulary

Epinephrine (EpiPen, EpiPen Jr)Effect: A1, A2, B1, B2 receptor agonist –

vasocontricts, relaxes bronchiole smooth muscle, increases heart rate

Dosage: EMTs: EpiPen (0.3ml) or EpiPen Jr (0.15ml)

Dosage: AEMTs: 0.3ml 1:1000 IM, or 0.15ml for 15-30kg

Dosage: Medics: as above, or 0.1-0.5mg iv 1:10,000 for anaphylaxis, 0.1mg/kg, max 1mg IV Q5 min for arrest

Indications: Anaphylaxis, severe asthma (medical control), cardiac arrest

Contraindications – noneSide Effects: arrhythmia, hypertension, MI,

jitteriness

EMT formulary

OxygenEffects: acts as a metabolic substrate for

respiration, energy productionDosage: 2-15lpm via NC (max 6lpm), or

oxymaskIndications: hypoxia, respiratory distress,

stroke like syndromesContraindications: open flameSide Effects: hyperoxia indicated in free radical

formation and increased cell damage.

EMT Formulary

Dextrose/GlucagonReviewed in Diabetic Emergencies Lecture

Diphenhydramine (Benadryl)Reviewed in Anaphylaxis Lecture

Naltrexone (Narcan)Effects: opioid receptor antagonistDosage: 0.4mg IV Q5 min until desired effect, max

2mgIndications: altered mental status, narcotic ODContraindications: alert patientSide Effects: pain, agitation, vomiting, injury to

EMT if patient not restrained.

AEMT formulary (State Mandated)

Benzodiazepines (diazepam/Valium; medazolam/Versed)Effects: GABA receptor agonist – increase seizure

threshold, sedating effectsDosage: Valium (long acting) .1-.2mg/kg IV, IM or PR

(gel) max 5-10mg x1 dose Versed (medium acting) .02-.05mg/kg max

4mg x1 Indications :Seizures, acute severe agitation, bath saltsContraindications: respiratory depression, sedation,

high risk airway, allergySide Effects: miosis, respiratory depression, need for

intubation

AEMT formulary

Narcotics (morphine; fentanyl)Effects: opioid agonist – provides pain reliefDosage: Morphine 0.1mg/kg IV/IM max 10mg for

pain Fentanyl – 0.5-1 mcg/kg iV max 50mcg x1

SLOWMedical control for any further dosingIndications: acute traumatic pain, cardiac pain

(morphine only)Contraindications: abdominal pain, allergy,

respiratory depression or altered mental statusSide Effects: Chest Wall Rigidity syndrome,

respiratory depression, hypotension

AEMT formulary

ZofranEffect: Reduction of nausea through inhibition

of serotonin 5-HT3 receptorDosage: 4mg IV/ODT for Adults and Children 6

and older 2mg IV/ODT children 2-6 1mg IV children 6 months-2 yearsIndications: nausea and vomitingContraindications: allergiesSide effects: may prolong QT, headache

Paramedic Formulary

PhenerganEffects: reduces nausea and vomiting via

dopamine receptor antagonismDosage: 25mg IM for adults only. Pediatric use

not permittedIndication: nausea and vomitingContraindication: sedation, allergySide Effects: respiratory depression,

extrapyramidal symptoms (dystonic reaction), anxiety, hypotension

Paramedic Formulary

HaldolEffects: sedation and reduction of psychotic

symptoms via dopamine receptor antagonismDosage: 2.5mg-5mg IM/2mg IVIndication: acute psychosis, severe agitation,

second line to maxing out your benzos for bath salts.

Contraindications: allergies, prolonged QT syndrome

Side Effects: sedation, Torades de Pointe, ventricular tachycardia, dystonia.

Paramedic Formulary

KetamineEffect: produces dissociative state through

limbic system interactionDosage: 1-2mg/kg IV or 3-4mg/kg IMIndications: induction agentContraindications: Theoretical – increased ICP,

increased IOP, allergySide effects: laryngospasm, emergence

reactions, excessive drooling

Paramedic Formulary

Paralytics (Rocuronium/Vecuronium)Effect: inhibits release of acetylcholine at the

neuromuscular junction causing paralysisDosage: Vecuronium: 0.1mg/kg IV Rocuronium: 1mg/kg IVIndications: paralytic agent for RSIContraindications: difficult airway, insuffient

expertise in airway managementAdverse Reactions: death

Paramedic Formulary

Solu-MedrolEffects: corticosteroid - reduces inflammation

and immunity through multiple messengers and interactions

Dosage: 1mg/kg IV, max 125mg IVIndications: asthma, COPD, anaphylaxisContraindications: allergySide Effect: hyperglycemia, jitteriness,

immunosuppression, renal impairment, GI bleeding

Paramedic Formulary

VasopressinEffect: hormone – constricts blood vessels and

improves cardiac contractilityDosage; 40 units x1 dose in lieu of first epi for

cardiac arrest.Indications: cardiac arrestContraindications: noneSide effects: none in prehospital setting

Paramedic Formulary

LidocaineEffects: Sodium Channel Blockade, inhibiting

nerve conduction for pain, and delaying ventricular automaticity

Dosage: V-tach/V-fib – 1mg/kg IV x1 IO needle pain – flush IO tubing with

lidocaine and push through with first normal saline flush

Indications – v-tach/v-fib, IO injection site painContraindications: allergySide effects: complete heart block, ventricular

arrest, seizures

Paramedic Formulary

MARK I KitEffects: Reverses the effects of

organophosphate poisonsDosage : 1 kit, repeat in 5 min as neededContains: Atropine 1mg 2-PAM Chloride 600mg Indications: organophosphate poisoning, WMD

eventContraindications: none in this settingSide Effects: blurred vision, headache,

dizziness, nausea, tachycardia

Paramedic Formulary

Magnesium SulfateEffect: relaxes smooth muscles in bronchioles,

uterus, stabilizes cardiac membranesDosage: 1-2 gm IV in adults over 20 minutes

for asthma (medical control required), 1-2gm IV push for Torsades

Indications: severe asthma, Torsades, preterm labor

Contraindications: hypermagnesemiaSide Effects: paralysis, respiratory depression

Paramedic Formulary

AmiodaroneEffect: Antiarrhythmic – multiple mechanismsDosage: 150mg IV for V-tach, 300mg IV for V-

fib arrestIndications: V-tach, V-fibContraindications: allergy, AV block,

pregnancy, breastfeedingSide Effects: lung fibrosis, AV block, Torsades

with other QT prolonging medications

Paramedic Formulary

AtropineEffect: antagonizes muscarinic receptors in

parasympathetic nervous systemDosage: 0.5mg-1mg IVIndication: Symptomatic BradycardiaContraindications: noneSide Effects: dry mouth, tachycardia,

jitteryness

Paramedic Formulary

HydroxocobalaminEffect: reverses cyanide toxicity by combining

with cyanide to make Vitamin B12Dosage:5gm IVIndications: cyanide ToxicityContraindications: caution for hemodialysis

patientsSide Effects: none

Paramedic Formulary

TetracaineEffect: anaesthetizes eye nerve ending through

sodium channel blockadeDosage: 1-2 gtts per eye, repeat PRNIndications: eye traumaContraindications: allergy to agent, open globeSide Effects: increasing tearing. Burning

Paramedic Formulary

AdenosineEffects: AV nodal blocking agentDosage: 0.05-0.1mg/kg up to 6mg IV RAPID

push, max 12mgIndications: SVTContraindications: wide complex tachycardia

with abberancy, WPWSide Effect: asystole (short lived), increased

HR with WPW.

Paramedic Formulary