A 40-year-old woman presents with mutism, negativism, and posturing of 4 days duration. To confirm the diagnosis of catatonia at the bedside, she is given an intravenous bolus of a single drug. Marked resolution of mutism and waxy flexibility occurs within 10 minutes. Which drug was administered?

• A Haloperidol 5 mg
• B Amobarbital sodium
• C Flumazenil 0.5 mg
• D Lorazepam 2 mg ✓

Explanation

The lorazepam challenge test uses 1 to 2 mg of intravenous lorazepam; a marked reduction in catatonic signs within 5 to 10 minutes confirms the diagnosis and predicts a good response to scheduled benzodiazepine therapy. Amobarbital was historically used for the narcosynthesis interview in mutism of hysterical origin, not for confirming catatonia. Haloperidol can worsen catatonia and precipitate neuroleptic malignant syndrome, and flumazenil reverses benzodiazepine action.

Reference: Kaplan and Sadock's Synopsis of Psychiatry, 12th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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