]> 2026-07-31T09:40:51+00:00 WBR0938 0 en Glucagon Glucagon counteracts beta-blocker toxicity by increasing intracellular cAMP. Epinephrine Epinephrine can be administered in the case of anaphylaxis. Digoxin While digoxin has an inotropic effect, it is not appropriate for counteracting beta-blocker overdose. Verapamil Verapamil is a calcium channel blocker that can be used to treat cardiac arrhythmias. It is not an effective antidote for beta-blocker overdose. Sotalol Sotalol is both a non-selective beta-blocker and potassium channel blocker (Class III antiarrhythmic). It is not an effective antidote for beta-blocker overdose. Non-selective beta-blockers such as propranolol interfere with the binding of catecholamine stress hormones such as epinephrine to beta-adrenergic receptors at most sites (β1-adrenergic receptors are located mainly in the heart and in the kidneys; β2-adrenergic receptors are located mainly in the lungs, gastrointestinal tract, liver, uterus, vascular smooth muscle, and skeletal muscle; β3-adrenergic receptors are located in fat cells). Because beta blockers decrease activity in the SA-node, they can lead to bradycardia and first degree heart block. In addition to arrhythmias, beta-blocker overdose may cause CNS depression and seizures. At the molecular level, beta-blockade causes a decrease in intracellular levels of cAMP. Glucagon binds to its G protein-coupled receptor, which then activates adenylate cyclase to increase intracellular levels of cAMP. This cascade counteracts the effects of beta-blocker overdose.<br/> '''Educational Objective:''' Glucagon counteracts beta-blocker toxicity by increasing intracellular cAMP.<br/> '''References:''' Weinstein RS, Cole S, Knaster HB, Dahlbert T (February 1985). "Beta blocker overdose with propranolol and with atenolol". Ann Emerg Med14 (2): 161–163 Pharmacology William J Gibson (Reviewed by Serge Korjian) A 60-year-old man attempts suicide by consuming his entire bottle of propranolol pills. He suffers extreme cardiovascular collapse and tonic-clonic seizures. Which of the following may serve as an antidote to his overdose? A Cardiology 2020-10-28T02:07:50Z 2459150.5887732 WBR0938