Intramuscular aripiprazole in the acute management of psychomotor agitation

Abstract

Study objective: To assess acute efficacy and safety of 9.75 mg of intramuscular (IM) injections of the atypical antipsychiatric aripiprazole in patients with schizophrenia or bipolar disorder and acute agitation.

Design: Open-label trial of IM injections of aripiprazole and 24-hour monitoring of clinical response in patients with major psychoses and acute agitation. Partial analysis of blood levels of the administered drug to correlate with clinical response.

Setting: Acute psychiatric care wards in a single university hospital.

Patients: A total of 201 acutely agitated patients (79 with schizophrenia and 122 with bipolar disorder I).

Intervention: Aripiprazole 9.75 mg IM injection.

Measurements and main results: We evaluated clinical response using the Excitatory Component of the Positive and Negative Syndrome Scale (PANSS-EC), the Agitation/Calmness Evaluation Scale (ACES), and the Clinical Global Impressions scale (CGI). Assessments were conducted 30, 60, 90, and 120 minutes and 24 hours after the first injection for PANSS-EC and ACES, and 2, 4, 6, and 24 hours for CGI. Response was at least a 40% decrease in PANSS-EC scores. We measured serum aripiprazole and dehydroaripiprazole levels in a subsample. IM aripiprazole significantly improved clinical measures. PANSS-EC improved progressively, starting after 30 minutes. ACES improved after 90 minutes and continued thereafter. Effects were sustained, with steadily decreasing CGI scores, until the 24th hour. Response rate was 83.6% after 2 hours, but with repeat injections, it rose to over 90% with no differences among diagnostic groups. Although there were gender differences in the response to individual PANSS-EC items, the responses were similar overall. Neither clinical monitoring nor patient reporting revealed any side effects. No therapeutic window was identified, and levels did not correlate with any clinical measure.

Conclusion: Aripiprazole was effective and safe in reducing acute agitation in patients with bipolar disorder or schizophrenia. Our results compare favorably to double-blind trials, probably due to higher expectations in trials involving no placebo arm. Absence of side effects could be related to the short observation time.