Toxicology USMLE Step 1 Practice Question
A 34-year-old woman arrives at the emergency department with somnolence after ingesting excessive diazepam. Vital signs show BP 118/76, HR 88, RR 10, temperature 37°C, and SpO2 98% on room air. Physical examination reveals normal pupils, no focal neurologic deficits, and intact gag reflex. Serum benzodiazepine level is elevated at 850 ng/mL. The team considers administering flumazenil as an antidote. Which mechanism best describes flumazenil's action?
Answer choices
- AStimulation of mu opioid receptors
- BIrreversible inhibition of monoamine oxidase
- CInhibition of alcohol dehydrogenase
- DBlockade of N methyl D aspartate receptors
- ECompetitive antagonism at the benzodiazepine binding site on the GABA A receptorCorrect answer
- FEnhancement of GABA reuptake from the synaptic cleft
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