Evidence for the effectiveness of olanzapine among patients nonresponsive and/or intolerant to risperidone.

Background: This multicenter, open-label study evaluated the efficacy and safety of olanzapine in patients with schizophrenia who had been nonresponsive or intolerant to a course of risperidone (mean duration of risperidone treatment = 46.3 days).

Method: A total of 34 patients with DSM-III-R and ICD-9 schizophrenia entered this trial.

The effectiveness of olanzapine in treatment-refractory schizophrenia when patients are nonresponsive to or unable to tolerate clozapine.

Objective: This multicenter, open-label study was designed to assess the efficacy and tolerability of olanzapine in patients with chronic schizophrenia who are resistant to therapy with classic neuroleptic agents and are either not responsive to or unable to tolerate clozapine.

Methods: Patients received olanzapine orally once daily for 18 weeks at doses ranging from 5 to 25 mg. The primary efficacy measure was change in the total score on the Positive and Negative Syndrome Scale (PANSS) from baseline to end point.