CNS Pharmacology USMLE Step 1 Practice Question
A 19-year-old male presents to the emergency department with acute onset agitation, palpitations, and tremor 3 hours after ingesting unknown pills at a party. He reports feeling "wired" and unable to sit still. Vital signs: temperature 37.9°C, heart rate 132 bpm, blood pressure 164/96 mmHg, respiratory rate 23 breaths/min. Physical examination reveals dilated pupils (6 mm), dry mucous membranes, hyperreflexia, and diaphoresis. An ECG shows sinus tachycardia without ischemic changes. Urine drug screen is positive for amphetamines. Which of the following is the most appropriate initial management?
Answer choices
- APropranolol 40 mg orally for rate control and blood pressure reduction
- BHaloperidol 5 mg IM for acute agitation
- CLorazepam 2-4 mg IV with supportive care, cooling measures, and cardiac monitoringCorrect answer
- DMethylphenidate 10 mg orally to counteract amphetamine effects
- EPhentolamine 5 mg IV followed by labetalol infusion
- FAmitriptyline 50 mg orally for sympathomimetic toxidrome management
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