EMT Chapter 12 (Pharmacology)

Acetaminophen (Tylenol)

Class: Analgesic, Antipyretic

Effects: Reduces pain and fever

Indications: Mild to moderate pain, fever

Contraindications: Severe liver disease, hypersensitivity (allergy)

MOA: Inhibits prostaglandin (hormone responsible for pain response) synthesis in CNS

Routes: Per Oral (PO), Per Rectal (PR), Intravenous (IV)

Side Effects: Hepatotoxicity (high doses), rash, nausea

Dose:

Adult: 500-1000 mg every 4-6 hrs (max 4000 mg/day)

Peds: 160-640 mg every 4-6 hrs (do not exceed more than 5 doses)

Activated Charcoal (Actidose)

Class: Adsorbent (a substance that adsorbs another)

Effects: Binds ingested toxins in GI tract

Indications: Poisonings/overdose (oral)

Contraindications: Altered LOC, caustic/hydrocarbon ingestion (chemicals that burn or corrode people's skin, eyes, and mucous membranes), GI obstruction

MOA: Adsorbs toxins → prevents systemic absorption

Routes: Per Oral (PO) or Nasogastric (NG) tube

Side Effects: Vomiting, aspiration, constipation

Dose:

Adult: 50-100 g Per Oral (PO)

Peds: 1 g/kg Per Oral (PO) (max 50 g)

Afrin (oxymetazoline)

Class: Alpha-adrenergic agonist

Effects: Vasoconstriction of blood vessels in nasal mucosa

Indications: Nasal Congestion, Sinus Pressure, Epistaxis (topical application)

Contraindications: Hypertension, glaucoma

MOA: Stimulates alpha receptors → vasoconstriction

Routes: Intranasal spray, Off-label use = topical application of the nasal spray

Side Effects: Rebound congestion (If used for more than 3 consecutive days), irritation, hypertension

Dose:

Adult: 2 sprays each nostril

Peds: 1-2 sprays (caution in under 6)

Albuterol (Ventolin, Proventil)

Class: Beta-2 agonist, bronchodilator

Effects: Relaxes bronchial smooth muscle

Indications: Asthma, COPD, bronchospasm

Contraindications: Hypersensitivity (allergy), tachyarrhythmias

MOA: Stimulates β2 receptors → bronchodilation

Routes: Inhaled (nebulizer or metered dose inhaler (MDI))

Side Effects: Tachycardia, tremor, nervousness

Dose:

Adult: 2.5 mg in 3 mL saline via nebulizer

Peds: 2.5 mg in 3 mL saline via nebulizer

Aspirin (ASA, Bayer)

Class: Antiplatelet, NSAID

Effects: Inhibits clot formation, reduces inflammation and pain

Indications: Chest pain of suspected cardiac origin

Contraindications: GI bleed, hemorrhagic stroke, allergy to NSAIDs

MOA: Irreversibly inhibits certain enzymes (called COX enzymes), which leads to a decrease in how well platelets stick together and form clots.

Routes: Per Oral (PO) (chewable preferred in EMS)

Side Effects: GI upset, bleeding, tinnitus (high dose)

Dose:

Adult: 160-325 mg chewed

Peds: Not recommended in EMS due to Reye's syndrome risk

Atropine/Pralidoxime (duodote)

Class: Anticholinergic / Cholinesterase reactivator (Anticholinergics block the action of acetylcholine, a chemical that helps nerves send signals, which helps calm down overactive nerve activity. Cholinesterase reactivators, on the other hand, fix an enzyme that breaks down acetylcholine. They're used when that enzyme gets blocked by poisons like nerve agents or pesticides. Together, these two drugs help treat dangerous poisonings by stopping the harmful effects of too much acetylcholine in the body.)

Effects: Reverses cholinergic symptoms (salivation, bradycardia, respiratory distress)

Indications: Nerve agent or organophosphate poisoning

Contraindications: None in emergency setting

MOA:

Atropine: Blocks ACh at muscarinic receptors (Acetylcholine receptors responsible for many parasympathetic reactions)

Pralidoxime: Reactivates AChE enzyme

Routes: IM (auto-injector)

Side Effects: Tachycardia, dry mouth, blurred vision, confusion

Dose:

Adult/Peds: 1 auto-injector IM (600 mg pralidoxime + 2 mg atropine); may repeat

Diphenhydramine (Benadryl)

Class: Antihistamine (H1 blocker)

Effects: Blocks histamine release, reduces allergic response

Indications: Allergic reactions, anaphylaxis (adjunct), motion sickness

Contraindications: Glaucoma, asthma (caution), Monoamine Oxidase Inhibitor (MAOI) - class of antidepressant

MOA: Competes with histamine at H1-receptor sites

Routes: Per Oral (PO), Intravenous (IV), Intramuscular (IM)

Side Effects: Drowsiness, dry mouth, dizziness

Dose:

Adult: 25-50 mg

Peds: 1 mg/kg (max 25-50 mg)

Epinephrine (Adrenalin)

Class: alpha- and beta-adrenergic agonists (sympathomimetic agents)

Effects: Bronchodilation, ↑ HR, ↑ BP

Indications: Anaphylaxis, asthma (severe), cardiac arrest

Contraindications: None in life-threatening situations

MOA: Stimulates alpha & beta receptors → vasoconstriction & bronchodilation

Routes: Intramuscular (IM), Intravenous (IV), Subcutaneous (SQ), Intranasal (IN) (cardiac arrest: Intravenous (IV)/Intraosseous (IO))

Side Effects: Tachycardia, hypertension, tremors, anxiety

Dose:

Adult: 0.3-0.5 mg IM (1:1000)

Peds: 0.01 mg/kg IM (max 0.3 mg)

Oral Glucose (Glutose, Insta-Glucose)

Class: Carbohydrate

Effects: Raises blood glucose

Indications: Hypoglycemia (conscious patient able to swallow)

Contraindications: Unconscious, unable to swallow

MOA: Absorbed through mucous membranes into bloodstream

Routes: Buccal (cheek), Per Oral (PO)

Side Effects: Nausea (might also be a symptom of the underlying low blood sugar (hypoglycemia)

Dose:

Adult & Peds: 15-30 g (3-4 tablets)

Glucagon (GlucaGen)

Class: Hormone

Effects: Increases blood glucose

Indications: Hypoglycemia (no IV access), beta-blocker overdose

Contraindications: Allergy, pheochromocytoma (Adrenal glad tumor)

MOA: Stimulates liver glycogen breakdown to glucose; Glucagon helps in a beta blocker overdose by using a backup route to get the heart beating faster and stronger, even when the usual adrenaline pathway is blocked.

Routes: Intramuscular (IM), Intranasal (IN), Intravenous (IV), Subcutaneous (SQ)

Side Effects: Nausea, vomiting, rebound hypoglycemia (Nausea and vomiting happen because glucagon affects the gut and triggers the brain's vomiting center.

Rebound hypoglycemia happens because glucagon's sugar-raising effect is short-term — once it wears off, blood sugar can crash again unless food is eaten.)

Dose:

Adult: 1 mg IM/IN

Peds: 0.5-1 mg IM/IN (age/weight dependent)

Naloxone (Narcan)

Class: Opioid antagonist

Effects: Reverses opioid respiratory depression/ Opiod induced CNS depression

Indications: Suspected opioid overdose

Contraindications: Hypersensitivity (allergy)

MOA: Competitively binds opioid receptors

Routes: Intranasal (IN), Intramuscular (IM), Subcutaneous (SQ), Intravenous (IV)

Side Effects: Withdrawal, agitation, tachycardia, nausea

Dose (for nasal dosage form):

Adults and children—At first, 3 to 10 milligrams (mg) (1 spray into one nostril). If needed, you may give more doses every 2 to 3 minutes until the patient responds or until emergency medical assistance becomes available. Use a new nasal spray for each dose and alternate nostrils each time.

Nitroglycerin (Nitrostat)

Class: Nitrate, vasodilator

Effects: Dilates coronary arteries, decreases preload (how much the heart fills with blood before it squeezes)-

Indications: Chest pain (MI, angina), CHF

Contraindications: SBP <100, ED meds, bradycardia, head injury

MOA: Converts to nitric oxide → smooth muscle relaxation

Routes: Sub lingual tablet/spray, transdermal, Intravenous (IV)

Side Effects: Hypotension, headache, dizziness

Dose:

Adult: 0.3-0.6 mg Sublingual; repeat every 5 mins ×3

Peds: Not typically used in prehospital pediatric care

Nitrous Oxide (Nitronox)

Class: Inhaled analgesic gas

Effects: CNS depression, euphoria, analgesia (pain relief)

Indications: Moderate to severe pain, anxiety

Contraindications: Pneumothorax, bowel obstruction, recent ear or eye surgury, hypertension, COPD, impaired consciousness and/or head injury

MOA: Depresses CNS → pain relief

Routes: Inhalation (50% N₂O/50% O₂ mix)

Side Effects: Dizziness, nausea, hypoxia (all sideffects can be lessened/prevented with administration of 100% oxygen for a few minutes after N2O cessation)

Dose:

Self-administered until relief or side effects occur

Peds: Can be used with proper mask and monitoring

Ibuprofen (Advil, Motrin)

Class: NSAID (Nonsteroidal Anti-Inflammatory Drug)

Effects: Reduces pain, fever, inflammation

Indications: Mild to moderate pain, fever

Contraindications: GI bleed, renal failure, allergy to NSAIDs

MOA: Inhibits certain enzymes (called COX enzymes), which leads to a decrease in prostaglandin synthesis (prostaglandin causes pain and inflammation when tissues are injured and raises body temperature)

Routes: Per Oral (PO)

Side Effects: GI irritation, ulcers, renal issues

Dose:

Adult: 200-800 mg every 6-8 hrs (max 3200 mg/day)

Peds: 10 mg/kg every 6-8 hrs (max 40 mg/kg/day)