Toxicology USMLE Step 1 Practice Question
A 38-year-old man with schizophrenia presents with fever, confusion, and altered mental status 3 days after initiating high-dose haloperidol. Vital signs show temperature 39.2°C, heart rate 118/min, blood pressure 152/94 mmHg, and respiratory rate 22/min. Physical examination demonstrates lead-pipe rigidity and diaphoresis. Laboratory studies reveal creatine kinase 2,840 U/L and normal liver function tests. Which of the following is the most likely diagnosis?
Answer choices
- ANeuroleptic malignant syndromeCorrect answer
- BMalignant hyperthermia
- CSerotonin syndrome
- DLithium toxicity
- EAnticholinergic toxicity
- FHaloperidol-induced acute dystonia with secondary infection
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