CNS Pharmacology USMLE Step 1 Practice Question
A 72-year-old woman with a 6-month history of insomnia presents to her primary care physician complaining of a concerning episode the night after starting zolpidem 10 mg at bedtime. She reports that approximately 3 hours after taking the medication, her husband found her standing in the kitchen preparing a meal, speaking unclearly, and appearing confused. She was unable to follow commands during this 15-minute episode. The next morning, she had complete amnesia for the event. She denies prior history of sleepwalking, takes no other CNS depressants or alcohol, and has normal renal and hepatic function. Her vital signs are stable and neurologic examination is unremarkable. Which of the following best explains this adverse effect?
Answer choices
- AZolpidem-induced delirium secondary to impaired hepatic clearance with accumulation to toxic levels
- BComplex sleep behavior occurring during NREM stage N2-N3 sleep with dissociation from wakefulnessCorrect answer
- CAcute anticholinergic toxicity from zolpidem's effects on cholinergic neurotransmission
- DREM sleep behavior disorder with loss of atonia and dream enactment during rapid eye movement sleep
- EMedication-induced psychosis from activation of dopaminergic pathways in the mesolimbic system
- FBenzodiazepine-like withdrawal syndrome despite ongoing zolpidem administration
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