RESUMEN
Objectives: To determine the antipsychotic efficacy and extra pyramidal safety of intramuscular olanzapine and intramuscular haloperidol during the first 24 hours of treatment of acute agitation in schizophrenia. Methods: Patients (n = 29) with schizophrenia were randomly allocated to receive one to three injections of intramuscular olanzapine (10 mg, n =14), intramuscular haloperidol (10 mg, n = 14) over a 24-hour period. Agitation was measured with the excited component of the positive and negative symptom scale (PANSS) and agitation behavior scale (ABS). Results: After the first injection, IM olanzapine was comparable to IM haloperidol for reducing mean changes in scores from baseline on excited component of PANSS at 2 hours to ( -13.08 olanzapine, -8.07 haloperidol ) and at 24 hours (-9.86 olanzapine, -8.07 haloperidol ). Mean changes in the scores of ABS scale from baseline was at 2 hours (-9.78 olanzapine, -8.54 haloperidol) and at 24 hours (-6.14 olanzapine, -6.6 haloperidol). Patients treated with IM olanzapine had significantly fewer incidence of treatment emergent Parkinsonism (0% olanzapine versus 6.66% haloperidol, p = 4.55), no patient had akathisia with olanzapine as compared to 13.33% of patients with haloperidol, p = 2.03. No patient developed acute dystonia compared to 6.66% of patients with haloperidol, p = 2.59. Conclusion: IM olanzapine was comparable to IM haloperidol in reduction of symptoms of acute agitation in schizophrenia during first 24 hours of treatment, the efficacy of both being evident within 2 hours after first injection. More Extra pyramidal symptoms were observed during treatment with IM haloperidol than with IM olanzapine.