Beta Blockers USMLE Step 1 Practice Question
A 4-year-old boy presents to the emergency department after ingesting multiple tablets from his grandfather's pill organizer. He is lethargic with BP 70/45 mmHg, HR 42 bpm, RR 18, and normal temperature. ECG demonstrates sinus bradycardia. Serum glucose is normal. He denies ingestion of other substances. Which of the following is the best pharmacologic agent to improve cardiac contractility and heart rate in this acute overdose setting?
Answer choices
- APhysostigmine
- BFlumazenil
- CNaloxone
- DMethacholine
- EGlucagonCorrect answer
- FCalcium chloride to overcome voltage-gated calcium channel blockade
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