Effect of clozapine in severe tardive dyskinesia: a case report.

There have been conflicting reports as to whether clozapine, an atypical antipsychotic, will suppress symptoms of tardive dyskinesia. With this in mind, the authors present the case of a 32-year-old chronically institutionalized schizophrenic who showed a remarkable improvement in both tardive dyskinesia and psychotic symptoms following an open trial of clozapine, 900 mg daily. This effect was noted to persist throughout the 15-month observation period with no breakthrough dyskinesia. The ability of clozapine to suppress tardive dyskinesia symptoms raises the possibility that clozapine, at least at the doses used in this report, might also induce the disorder. Long-term, controlled studies are required to specifically address this issue.