If heart rate is less than 50 and systolic blood pressure is less than 90 in a beta-blocker overdose, what medication is administered first?

In cases of beta-blocker overdose, bradycardia (heart rate less than 50) and hypotension (systolic blood pressure less than 90) are significant concerns that require immediate intervention. Atropine is an anticholinergic medication that can help increase heart rate by blocking vagal tone and facilitating conduction through the AV node. Administering 1 mg IV of atropine is appropriate in this situation because it is typically given in larger doses for more severe bradycardic episodes.

Using a higher dose of atropine, such as 1 mg, is more effective in responding to the demands of a beta-blocker overdose, where traditional doses may not sufficiently combat the adrenergic blockade caused by the beta-blockers. The goal of atropine in this context is to temporarily relieve bradycardia and stabilize the patient's condition while further treatments can be arranged.

Other medications listed, while potentially appropriate for different scenarios, may not address the immediate need for increasing heart rate effectively in this situation.