CNS Pharmacology USMLE Step 1 Practice Question
A 67-year-old man treated with a class III antiarrhythmic for recurrent ventricular tachycardia presents with progressive dyspnea and cough over six months. Vital signs show HR 78/min, BP 138/92 mmHg, RR 22/min, SpO2 92% on room air. Physical examination reveals blue-gray skin discoloration and photosensitivity. Laboratory studies show elevated transaminases (AST 145 U/L). Chest X-ray demonstrates pulmonary fibrosis. He denies orthopnea. Which antiarrhythmic drug most likely caused these findings?
Answer choices
- AQuinidine
- BSotalol
- CAmiodaroneCorrect answer
- DLidocaine
- EDiltiazem
- FFlecainide
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