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Rapid Tranquillisation — MRCPsych Paper B MCQ

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ModerateSchizophrenia & PsychosisRapid TranquillisationMRCPsych Paper B

A 45-year-old woman with bipolar I disorder is manic with psychotic features. Despite attempted de-escalation, she remains severely agitated and is threatening immediate violence towards staff. She refuses oral medication, and rapid tranquillisation is required. During a previous admission, IM lorazepam caused marked paradoxical agitation, whereas IM haloperidol with IM promethazine was effective and well tolerated. Her ECG today shows a normal QTc interval, and she has no cardiovascular disease, relevant drug interactions or evidence of intoxication. Which is the most appropriate initial IM option?

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Correct answer: D — IM haloperidol plus IM promethazine

NICE recommends either IM lorazepam alone or IM haloperidol combined with IM promethazine for rapid tranquillisation in adults, with the choice individualised according to previous response and adverse effects, physical health, intoxication, interactions and ECG findings. Here, previous paradoxical agitation with lorazepam makes option C unsuitable, while the haloperidol–promethazine combination was previously effective and tolerated. A current normal ECG and absence of cardiovascular disease support its use. IM olanzapine and IM aripiprazole are not the standard regimens recommended by NICE NG10 for this situation. IM diazepam is also not a recommended rapid-tranquillisation regimen. If no ECG had been obtained, cardiovascular disease were present, or the medication history were insufficient, IM lorazepam would instead be preferred.

Reference: National Institute for Health and Care Excellence. Violence and aggression: short-term management in mental health, health and community settings. NICE guideline NG10, recommendations 1.4.37–1.4.39. 2015. https://www.nice.org.uk/guidance/ng10/chapter/recommendations