Toxicology USMLE Step 1 Practice Question
A 49-year-old man with severe alcohol use disorder presents with confusion, ataxia, and poor oral intake for 3 days. Vitals: BP 118/76, HR 102, RR 16, Temp 37.2°C, SpO2 98%. Laboratory studies show serum glucose 52 mg/dL and thiamine level 1.2 nmol/L (normal >5.3). He denies nystagmus. Intravenous dextrose-containing fluids are planned. Which medication should be administered first to prevent Wernicke encephalopathy?
Answer choices
- AThiamineCorrect answer
- BVitamin C
- CPyridoxine
- DFolate
- ECyanocobalamin
- FRiboflavin (vitamin B2)
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