Parenteral haloperidol for rapid control of severe, disruptive symptoms of acute schizophrenia.

Intramuscular haloperidol, at three dose levels, (5 mg, 2 mg, and 1 mg) chlorpromazine (25 mg), and placebo were compared for efficacy, rapidity of therapeutic onset, and safety in 50 acute psychotic patients requiring rapid control. The drugs were administered parenterally under double-blind conditions at half-hour intervals until successful control of moderate to very severe symptomatology was achieved or a maximum of four injections had been given. Global evaluation, BPRS, and target symptom ratings were performed. The overall results indicated that the 5 mg and 2 mg haloperidol doses were significantly superior to the 1 mg haloperidol and 25 mg chlorpromazine doses and to placebo. Transfer of patients to oral haloperidol was satisfactorily accomplished. Side effects for all medications were minimal and included slight to moderate EPS and drowsiness. The use of antiparkinson drugs completely controlled the extrapyramidal symptoms.