Vitamin E in the treatment of tardive dyskinesia: a preliminary study over 7 months at different doses.

Vitamin E has been suggested to be a promising new treatment for tardive dyskinesia. However, little is known about the optimum dose. Twenty patients with tardive dyskinesia whose medication had been unchanged for at least 1 month were selected and randomly divided into a treatment group with 11 patients and a control group with nine patients. The treatment group was started on 600 mg of vitamin E per day, and this dose was increased over the 7 months of the trial to 1600 mg per day. The medication for the control group was unchanged. Severity of tardive dyskinesia was rated on the Abnormal Involuntary Movement Scale. Patients in the treatment group initially showed a significant response to the lower dose of 600 mg per day. However, this improvement was not maintained and differences between the two groups reached significant levels only after the dose of vitamin E was increased to 1600 mg per day. At this dose, there was a significant and sustained reduction in the severity of tardive dyskinesia. The results suggest that vitamin E is of value in the treatment of tardive dyskinesia and that the optimum dose for treating tardive dyskinesia is 1600 mg per day. In addition, there may be a dose related therapeutic effect of Vitamin E in tardive dyskinesia.