Abstract
Many psychiatric illnesses, including chronic schizophrenia, bipolar disorder, and dementia, are characterized by episodes of acute agitation, making administration of oral agents difficult or impossible. Ziprasidone, the first atypical antipsychotic available in both intramuscular (IM) and oral formulations, has demonstrated significant control of acute agitation within 15 minutes, as seen in two 24-hour studies in patients with schizophrenia. Improvement was maintained for ≥ 4 hours, and a low incidence of extrapyramidal symptoms, akathisia, and dystonia as well as no excessive sedation were observed. Also, two 7-day studies (n = 132 and n = 306) and one 6-week study (n = 567) of sequential IM/oral ziprasidone versus IM/oral haloperidol in patients with psychotic disorders found IM ziprasidone more effective than IM haloperidol within 3 days of IM treatment; both drugs produced further comparable improvements in efficacy parameters after transition to oral therapy. IM ziprasidone was associated with a lower incidence of movement disorders than was haloperidol in all of these studies. Overall, discontinuations were similar for IM ziprasidone and haloperidol in the comparative trials, including the sequential IM/oral studies. However, in the 6-week sequential IM/oral trial, the rate of discontinuation due to adverse events was twice as high among haloperidol vs ziprasidone patients. This report focuses on the pharmacology, clinical efficacy, and tolerability of IM ziprasidone, and provides an overview of the utility of other commonly used antipsychotics in the management of acute psychotic agitation.