Intramuscular ziprasidone: moving beyond the conventional in the treatment of acute agitation in schizophrenia.

The appropriate management of schizophrenia and schizoaffective disorder requires effective, safe antipsychotic agents for use across a continuum of treatment, from control of acute psychotic episodes to prevention of relapse. Intramuscular (IM) formulations are the method of choice for administering antipsychotics to schizophrenic patients who require emergency treatment but cannot take oral medication. Atypical antipsychotics are now widely acknowledged as the first-line choice for the management of patients with schizophrenia. However, use of these agents in acutely agitated psychotic patients has been limited by the lack of an IM formulation. Ziprasidone is the first, and currently only, atypical antipsychotic to be available in a rapid-acting IM formulation. This review focuses on studies evaluating the efficacy and tolerability of IM ziprasidone. In agitated psychotic patients, IM ziprasidone reduces agitation as early as 15 minutes after administration, with improvement sustained for > or = 4 hours. In patients with acute psychosis, with or without agitation, IM ziprasidone has been demonstrated to be superior to IM haloperidol in improving overall symptom severity. During the critical IM-to-oral transition, efficacy and tolerability are maintained with ziprasidone. IM ziprasidone represents an important advance over older, conventional IM agents in the treatment of the acutely ill patient with schizophrenia.