A combative patient receives intramuscular olanzapine 10 mg for acute agitation. Thirty minutes later he remains agitated and the team considers adding a second agent. Which combination must be avoided at this point?

• A Intramuscular haloperidol within one hour of the olanzapine injection
• B Intramuscular lorazepam within one hour of the olanzapine injection ✓
• C Oral diazepam four hours after the olanzapine injection
• D Oral quetiapine six hours after the olanzapine injection

Explanation

Parenteral olanzapine combined with a parenteral benzodiazepine within one hour causes unpredictable cardiorespiratory depression and sudden death, so product labeling advises against this interval. An additional antipsychotic given later, or oral sedatives after adequate time, does not carry the same warning. This timing rule is a standard safety point in rapid tranquillisation protocols followed in Indian emergency settings.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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