A 45-year-old man with known bipolar disorder presents in the ER with severe psychomotor agitation, threatening to harm others. He refuses oral medication. According to evidence-based rapid tranquillisation protocols, what is the PREFERRED combination for IM administration?

• A Chlorpromazine 100 mg + diazepam 10 mg IM
• B Olanzapine 10 mg IM + lorazepam 2 mg IM simultaneously
• C Haloperidol 5 mg + promethazine 25 mg IM ✓
• D Droperidol 10 mg IM alone

Explanation

Haloperidol + promethazine IM is one of the most evidence-based rapid tranquillisation regimens (supported by the TRASA/Cochrane evidence), combining the antipsychotic effect of haloperidol with the sedative/antihistaminic effect of promethazine to reduce agitation with a better side-effect profile than haloperidol alone. Combining olanzapine IM with benzodiazepines IM is contraindicated due to risk of fatal respiratory depression and cardiac arrest. Diazepam should not be given IM (poor absorption); chlorpromazine IM can cause profound hypotension.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.