A 19-year-old man develops painful upward deviation of the eyes, trismus, and torticollis 36 hours after starting haloperidol. He is conscious and afebrile. Which of the following is the most appropriate immediate treatment?

• A Intravenous dantrolene
• B Intravenous lorazepam infusion
• C Oral propranolol
• D Intramuscular promethazine or another anticholinergic ✓

Explanation

This is an acute drug-induced dystonic reaction, common in young males within days of starting a high-potency typical antipsychotic. It resolves promptly with parenteral anticholinergics such as promethazine or benztropine, or with antihistamines. Dantrolene is specific for neuroleptic malignant syndrome, which this patient does not have because he lacks hyperthermia, rigidity, and autonomic instability. Propranolol treats akathisia, and lorazepam infusion is not standard for acute dystonia.

Reference: Kaplan and Sadock's Synopsis of Psychiatry, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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