Efficacy and Safety of Olanzapine in the Treatment of Thai Schizophrenic Patients

Abstract

Olanzapine is a thienobenzodiazepine derivative which displays efficacy in patients with schizophrenia and related psychoses. It has structural and pharmacological properties resembling those of atypical antipsychotic (clozapine) and an improved tolerability profile compared with the classical antipsychotic drugs. The purpose of this study was to evaluate the efficacy, tolerability and safety of olanzapine in chronic schizophrenic patients. In an open label study, 10 patients with schizophrenia (DSM-IV), who met the inclusion criteria (CGI score of at least 3, 18 to 65 years of age, no serious unstable medical illnesses), were assigned to receive olanzapine for six weeks after a wash-out period of at least these drugs. Dosages were started at 10 mg/day for at least five days and then adjusted according to each patient’s response, but not increased to no more than 20 mg/day. Treatment efficacy, safety and tolerability were evaluated with several well-known rating scales and blood chemistry. Olanzapine significantly reduced the severity of psychotic symptoms (score on clinical global improvement, brief psychiatric rating scale, and positive and negative syndrome scales) from baseline. At the end point, all the subjects were found to have clinically improved (a reduction in total positive and negative syndrome scale and reduction of 40.38 - 76.22 percent in Clinical global improvement). The only side-effects of Olanzapine appeared to be weight gain and drowsiness that was mild in severity with no reports of extrapyramidal side- effects. It was concluded that Olanzapine was well tolerated and effective in treating either positive or negative symptoms in patients with schizophrenia.