Effects of switching inpatients with treatment-resistant schizophrenia from clozapine to risperidone.

A prospective, open-label study in a 400-bed state psychiatric hospital evaluated change in therapeutic response among ten patients with treatment-resistant schizophrenia who were switched from clozapine to risperidone. Drug effects were examined before discontinuation of clozapine and at three, six, nine, and 12 weeks of risperidone treatment. No patients improved, and five discontinued treatment due to exacerbation of psychosis or adverse effects. Changes in scores on the Positive and Negative Syndrome Scale, the Brief Psychiatric Rating Scale, and the Barnes Akathisia Scale indicated clinically significant worsening of symptoms. The findings do not support replacing clozapine with risperidone for patients with treatment-resistant schizophrenia.