Toxicology USMLE Step 1 Practice Question
A 45-year-old man with alcohol use disorder presents with acute flushing, throbbing headache, nausea, palpitations, and diaphoresis 15 minutes after consuming one beer. Vital signs: BP 156/92 mmHg, HR 108 bpm, RR 18, temp 37.2°C. He denies chest pain or dyspnea. His medication list includes a recently initiated agent for alcohol cessation. Serum acetaldehyde level is elevated at 89 μmol/L. Inhibition of which enzyme most directly explains this disulfiram-like reaction?
Answer choices
- ACytochrome oxidase
- BAldehyde dehydrogenaseCorrect answer
- CXanthine oxidase
- DAlcohol dehydrogenase
- EDihydrofolate reductase
- FMonoamine oxidase
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