Intramuscular (IM) ziprasidone 20 mg is effective in reducing acute agitation associated with psychosis: a...

Intramuscular (IM) conventional antipsychotics and/or benzodiazepines are effective in the short-term treatment of acutely agitated psychotic patients but may be associated with adverse effects. A short-acting IM formulation of the novel antipsychotic, ziprasidone, which may offer advantages over conventional agents, has been developed.

To compare ziprasidone IM 2 mg (n=38) and 20 mg (n=41) in the acute control and short-term management of agitated psychotic patients.

A prospective, randomized, double-blind, 24-h study assessed efficacy using the Behavioral Activity Rating Scale (BARS) and the PANSS. The BARS is a validated rating scale for the assessment of treatment response in acute agitation associated with psychosis. Following the initial dose, three more doses could be given 4 h apart if needed during the 24-h period.

The mean BARS score had decreased 15 min after the first 20 mg IM dose and was statistically significantly lower than the 2 mg group at 30 min post-dose. The improvement with the 20 mg dose increased until 2 h, and was maintained until at least 4 h post-dose (P<0.001). Two hours after the first injection, almost all of the patients receiving ziprasidone 20 mg were BARS responders compared with just one-third of those receiving 2 mg ziprasidone (P<0.001). The calming effect of ziprasidone was also evident by the significant reduction in PANSS agitation items (P<0.05) and CGI-severity at 4 h (P=0.008). Both ziprasidone doses were very well tolerated. Ziprasidone IM 20 mg was not associated with EPS, dystonia, akathisia, respiratory depression or with excessive sedation.

Ziprasidone IM 20 mg substantially and significantly reduced the symptoms of acute agitation in patients with psychotic disorders. Ziprasidone 20 mg IM was very well tolerated and produced no dystonia or akathisia.