An open trial of clozapine for dystonia

Pharmacologic treatment of seven dystonia is often unsatisfactory. The atyp ical antipsychotic medication clozapine appears to improve tardive dystonia associated with conventional neuroleptic use. We studied the efficacy of c lozapine for severe dystonia in five patients in an open trial. The patient cohort included four with generalized dystonia and one with Meige syndrome . All patients were evaluated at baseline and at least weekly while on medi cation with subjective assessment of response by the patient and physician rating using the Burke-Fahn-Marsden Evaluation Scale for Dystonia. All five subjects had significant improvement detected by the Burke-Fahn-Marsden Ev aluation Scale as well as subjective improvement while on clozapine. Side e ffects, such as sedation and orthostatic hypotension, developed in all pati ents but was only treatment-limiting in one subject who developed persisten t symptomatic orthostatic hypotension and tachycardia. Two of the four rema ining patients continued clozapine after completion of the study; an additi onal patient was uncertain if the benefit outweighed the side effects, One patient discontinued treatment because of difficulty obtaining the FDA-requ ired weekly white blood cell counts for patients on clozapine. We conclude that clozapine appears to be effective for generalized and refractory focal dystonia although its use may be limited by the side effects and need for hematologic monitoring.