Beta Blockers USMLE Step 1 Practice Question
A 27-year-old woman with myasthenia gravis undergoes thymectomy. Postoperatively, she develops abdominal distention, absent bowel sounds, and nausea consistent with ileus. Vital signs: BP 118/76, HR 92, RR 16, temp 37.2°C. Labs show normal electrolytes and serum creatinine 0.9 mg/dL. She has no respiratory distress. To reverse postoperative ileus while avoiding CNS effects, she receives a reversible acetylcholinesterase inhibitor that does not cross the blood-brain barrier. Which drug was most likely administered?
Answer choices
- ADonepezil
- BAtropine
- CNeostigmineCorrect answer
- DPhysostigmine
- EEdrophonium
- FPyridostigmine
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