A double-blind, randomized comparison of the efficacy and safety of intramuscular injections of olanzapine, lorazepam, or placebo in treating acutelyagitated patients diagnosed with bipolar mania

There are no rapid-acting intramuscular formulations of atypical antipsycho tics available for quickly calming an agitated patient with bipolar disorde r. In this study, 201 agitated patients with bipolar mania were randomly as signed to receive one to three injections of the atypical antipsychotic ola nzapine (10 mg, first two injections; 5 mg, third injection), the benzodiaz epine lorazepam (2 mg, first two injections; 1 mg, third injection), or pla cebo (placebo, first two injections; olanzapine, 10 mg, third injection) wi thin a 24-hour period. Agitation was measured at baseline, every 30 minutes for the first 2 hours, and at 24 hours after the first injection using the Positive and Negative Syndrome Scale-Excited Component subscale and two ad ditional agitation scales. At 2 hours after the first injection, patients t reated with olanzapine showed a significantly greater reduction in scores o n all agitation scales compared with patients treated with either placebo o r lorazepam. At 24 hours after the first injection, olanzapine remained sta tistically superior to placebo in reducing agitation in patients with acute mania, whereas patients treated with lorazepam were not significantly diff erent from those treated with placebo or olanzapine. Furthermore, no signif icant differences among the three treatment groups were observed in safety measures, including treatment-emergent extrapyramidal symptoms, the inciden ce of acute dystonia, or QTc interval changes. These findings suggest that intramuscular olanzapine is a safe and effective treatment for reducing acu te agitation in patients with bipolar mania.