For a patient experiencing a severe beta-blocker overdose, what medication would be administered?

• A. Flumazenil
• B. Glucagon
• C. N-acetylcysteine
• D. Deferoxamine

Answer: (B)

In the case of a severe beta-blocker overdose, administering glucagon is a highly effective treatment. Glucagon acts by increasing cyclic AMP levels in cardiac tissue, which counteracts the negative inotropic effects of beta-blockers and can help restore heart rate and improve cardiac output. It also bypasses the beta-adrenergic receptors, making it particularly useful for reversing the effects of beta-blockers, especially in cases where patients may not respond to conventional treatment options such as fluids or atropine.

Patients experiencing beta-blocker toxicity may present with symptoms such as bradycardia, hypotension, and heart failure. The use of glucagon can also help manage this condition by facilitating gluconeogenesis, which leads to an increase in blood sugar levels, and in turn, enhances myocardial energy substrate availability. This multifaceted action makes glucagon the most appropriate choice for addressing the complications of a severe beta-blocker overdose.

Other medications listed do not have the same targeted benefits for beta-blocker overdose, making glucagon the ideal intervention in this scenario.