Background: We conducted a naturalistic, multicenter, 24-hour, nonrandomized, observational study describing for the first time the effectiveness and safety of intramuscular (IM) olanzapine to control agitation and aggression in "real world" patients with psychosis. The data thus obtained was compared with that reported from randomized double-blind clinical trials.
Method: 92 patients attending psychiatric emergency settings were enrolled. The study subjects were 44 male and 48 female patients with a mean age of 36.5+/-12 years and DSM-IV-TR diagnoses of schizophrenia (48.9%), psychotic disorder not specified (23.9%) or bipolar disorder (27.2%). 10 mg IM olanzapine was administered to all patients. An optional second injection was permitted> or =2 hours later in line with hospital policy. Evaluations (PANSS-EC and CGI-S) were performed at baseline and 2 and 24 hours following the IM injection.
Results: Two hours after IM olanzapine was administered, a mean decrease of -9.6 in the PANSS-EC from a baseline score of 26.5 was recorded. At the 24-hour endpoint a statistically and clinically significant reduction in the PANSS-EC scores (11.6+/-5.3) was observed as compared with values at study entry (26.5+/-5.9) and at 2 hours endpoint (16.9+/-9.3), which represent a mean decrease of -14.9 and -5.3, respectively.
Conclusion: The present naturalistic study provides naturalistic data on the effectiveness of IM olanzapine in the treatment of acute agitation in patients with schizophrenia or bipolar mania that is in line the data obtained in randomized double-blind clinical trials.