Adrenaline

• Approved Indications:
• Emergency treatment of anaphylaxis and severe allergic reactions.
• Cardiac arrest (asystole, pulseless ventricular tachycardia/fibrillation) during advanced cardiac life support (ACLS).
• Severe bronchospasm or acute asthma exacerbations unresponsive to initial therapies.
• Hypotension or shock refractory to fluid resuscitation, including septic shock adjunctive use.
• Important Off-label (Clinically Accepted) Uses:
• Local vasoconstrictor to prolong anesthetic effect during regional anesthesia.
• Control of superficial bleeding in surgical procedures.
• Treatment of croup via nebulized epinephrine.

• Adults:
• Anaphylaxis: 0.3–0.5 mg intramuscular (IM) every 5–15 minutes as needed.
• Cardiac arrest: 1 mg intravenous (IV) or intraosseous (IO) every 3–5 minutes during resuscitation.
• Severe bronchospasm: 0.3–0.5 mg IM or subcutaneous (SC); nebulized doses vary (2.25% solution, 0.25–0.5 mL diluted).
• Hypotension/shock: Titrated IV infusion starting at 1 mcg/min, adjusted per clinical response.
• Pediatrics:
• Anaphylaxis: 0.01 mg/kg IM, max 0.3 mg per dose, repeat every 5–15 minutes as needed.
• Cardiac arrest: 0.01 mg/kg IV/IO every 3–5 minutes.
• Bronchospasm: Similar dosing adjusted by weight; nebulized epinephrine 0.05–0.1 mL/kg of 1:1000 solution.
• Elderly:
• Use standard dosing but monitor closely due to increased cardiovascular risk.
• Special Populations:
• Use cautiously in patients with cardiovascular disease; no specific dose adjustment for renal or hepatic impairment.

Adrenaline is a non-selective adrenergic agonist acting on alpha-1, alpha-2, beta-1, and beta-2 adrenergic receptors. Activation of alpha-1 receptors causes vasoconstriction, increasing peripheral vascular resistance and raising blood pressure. Beta-1 receptor stimulation enhances heart rate, myocardial contractility, and conduction velocity, supporting cardiac output during cardiac arrest. Beta-2 receptor activation leads to bronchodilation and relaxation of smooth muscles in the airways, facilitating breathing. The combined receptor activation results in rapid reversal of anaphylactic symptoms, increased coronary and cerebral perfusion during resuscitation, and relief of bronchospasm.

• Absorption: Rapid following IM, SC, or IV administration. IM absorption is slower but more sustained than IV.
• Distribution: Widely distributed in the body; crosses placenta but not significantly the blood-brain barrier.
• Metabolism: Primarily metabolized by catechol-O-methyltransferase (COMT) and monoamine oxidase (MAO) enzymes in the liver and other tissues.
• Elimination: Metabolites excreted via urine.
• Half-life: Approximately 2–3 minutes due to rapid metabolism.

• Pregnancy: Category C (FDA); use only if potential benefit justifies potential risk to fetus. Adrenaline may reduce uterine blood flow due to vasoconstriction.
• Lactation: Excreted in breast milk in small amounts; effects on nursing infants unknown but considered low risk due to rapid metabolism.

• Sympathomimetic agent / Adrenergic agonist
• Subclass: Non-selective adrenergic agonist

• Known hypersensitivity to adrenaline or formulation excipients.
• Narrow-angle glaucoma (relative contraindication).
• Certain cardiac arrhythmias without cardiac arrest (use with caution).
• Use with non-selective beta-blockers may precipitate hypertension or bradycardia.

• Use cautiously in patients with cardiovascular disease, hypertension, hyperthyroidism, diabetes mellitus, or prostatic hypertrophy.
• May cause severe hypertension, arrhythmias, myocardial ischemia, or cerebral hemorrhage if overdosed or improperly administered.
• Monitor cardiovascular status continuously during IV infusion.
• Avoid inadvertent intra-arterial injection due to risk of tissue necrosis.
• Early signs of overdose include palpitations, headache, tremor, and anxiety.

• Common:
• Palpitations, tachycardia
• Anxiety, restlessness, tremor
• Headache
• Sweating, pallor
• Serious/Rare:
• Severe hypertension, arrhythmias
• Myocardial ischemia or infarction
• Pulmonary edema
• Necrosis or ischemia at injection site (especially with extravasation)

• Increased toxicity or reduced efficacy with:
• Non-selective beta-blockers (may cause unopposed alpha stimulation → hypertension)
• MAO inhibitors and tricyclic antidepressants (potentiate effects and toxicity)
• Alpha- and beta-adrenergic agents (additive effects)
• Digoxin (risk of arrhythmias increased)
• Beta-agonists or other sympathomimetics (additive cardiac stimulation)
• Avoid alcohol and CNS depressants concurrently to prevent unpredictable CNS effects.

• Current ACLS guidelines reaffirm adrenaline’s role as a first-line agent in cardiac arrest and anaphylaxis management.
• Updated recommendations emphasize IM administration as preferred route for anaphylaxis due to safety and efficacy.
• No major recent changes in dosing but increased awareness of potential adverse cardiovascular effects in elderly and comorbid patients.

• Store at 20°C to 25°C (68°F to 77°F).
• Protect from light and freezing.
• Keep ampules or prefilled syringes in original packaging until use.
• Avoid excessive agitation or shaking.
• Discard if solution is discolored or contains particulate matter.