Toxicology USMLE Step 1 Practice Question
A 32-year-old man on isoniazid for latent tuberculosis presents after intentionally ingesting an unknown quantity of his medications. He is febrile (38.5°C), tachycardic (118 bpm), tachypneic (22 bpm), with BP 132/88 mmHg. He has refractory generalized seizures unresponsive to benzodiazepines and lorazepam. Laboratory studies reveal a high anion gap metabolic acidosis (pH 7.18, AG 16). Serum glucose is normal. Which medication is the most appropriate antidotal therapy?
Answer choices
- AMethylene blue
- BN-acetylcysteine
- CFolate
- DThiamine
- EPyridoxineCorrect answer
- FHydroxocobalamin
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