Rapid tranquillisation in a psychiatric emergency hospital in Lebanon: TREC-Lebanon - a pragmatic randomised controlled trial of intramuscular haloperidol and promethazine v. intramuscular haloperidol, promethazine and chlorpromazine.

Neither intervention consistently impacted the outcome of 'calm', or 'asleep' and had no discernible effect on the use of restraints, use of additional drugs or recurrence. If clinicians are faced with uncertainty on which of the two intervention combinations to use, the simpler HP is much more widely tested and the addition of chlorpromazine adds no clear benefit with a risk of additional adverse effects.