Intramuscular Ziprasidone, 2 mg Versus 10 mg, in the Short-Term Management of Agitated Psychotic Patients

Background: There is a clear need for effective, well-tolerated intramuscular (i.m.) agents for the acute control of agitated psychotic patients. Currently used agents, including conventional antipsychotics and/or benzodiazepines, may be associated with distressing side effects such as extrapyramidal side effects and excessive sedation.

Objective: The objective of this study was to evaluate the efficacy and tolerability of the rapid-acting i.m. formulation of the novel antipsychotic ziprasidone in the treatment of inpatients with psychosis and acute agitation (DSM-IV diagnoses).

Method: In a 24-hour, double-blind, fixed-dose clinical trial, patients were randomly assigned to receive up to 4 injections (every 2 hours p.r.n.) of 2 mg (N = 54) or 10 mg (N = 63) of ziprasidone i.m. The Behavioral Activity Rating Scale measured behavioral symptoms at baseline and the response to treatment up to 4 hours after the first i.m. injection.

Results: Ziprasidone i.m., 10 mg, rapidly reduced symptoms of acute agitation and was significantly more effective (p < .01) than the 2-mg dose up to 4 hours after the first injection. Patients were calmed but not excessively sedated, and over half were classed as responders 2 hours after the 10-mg dose. No acute dystonia or behavioral disinhibition was reported. One patient who received the 10-mg dose experienced the extrapyramidal side effect akathisia.

Conclusion: Ziprasidone i.m., 10 mg, is rapidly effective and well tolerated in the short-term management of the agitated psychotic patient. Comparison with a study of identical design comparing 2-mg with 20-mg doses in patients with similar levels of psychopathology suggests that efficacy with 10 mg or 20 mg of ziprasidone i.m. is significant and dose related.

J Clin Psychiatry 2001;62(1):12-18