epinephrine + propranolol

Epinephrine + propranolol is a combination of two pharmacologically active agents with opposing actions on the adrenergic system. Epinephrine (adrenaline) is a hormone and neurotransmitter that acts as an agonist at both alpha- and beta-adrenergic receptors, leading to increased heart rate, vasoconstriction, bronchodilation, and other sympathetic effects. It is used in emergency medicine for anaphylaxis, cardiac arrest, asthma exacerbations, and as a vasoconstrictor adjunct in local anesthesia[4]. Propranolol is a non-selective beta-adrenergic receptor antagonist (beta blocker) that reduces heart rate and myocardial contractility by blocking the effects of endogenous catecholamines like epinephrine and norepinephrine[6][8][10]. It is indicated for hypertension, angina pectoris, arrhythmias, migraine prophylaxis, essential tremor, anxiety disorders, among others[5][6][8][10]. When combined—intentionally or unintentionally—propranolol blocks the beta-mediated effects of epinephrine while leaving alpha-mediated vasoconstriction unopposed. This can result in severe hypertension and bradycardia due to unopposed alpha-adrenergic stimulation by epinephrine[7][9]. The combination does not have recognized therapeutic use due to this dangerous interaction; it is generally contraindicated except under special circumstances.