What is the next drug administered for beta-blocker overdose in cases of bradycardia?

In the context of a beta-blocker overdose accompanied by bradycardia, administering glucagon is the recommended course of action. Glucagon works by increasing heart rate and improving cardiac output, as it effectively counters the effects of beta-blocker toxicity. It stimulates the adenylate cyclase pathway, ultimately leading to increased levels of cyclic AMP in cardiomyocytes, which enhances myocardial contractility and can alleviate bradycardia.

Glucagon is particularly advantageous in this scenario because it does not rely on beta-adrenergic receptors to function, making it suitable in situations where those receptors are inhibited due to the effects of beta-blockers. Consequently, when bradycardia results from an overdose of beta-blocking agents, glucagon can effectively mitigate these effects and restore heart rate.

The alternatives offered, while relevant in other contexts, do not specifically address the mechanism or treatment efficacy against beta-blocker overdose.