Treatment of tardive dyskinesias with vitamin E*

Abstract

SummaryThe hypothesis that tardive dyskinesias observed after long-term administration of neuroleptics are due to the formation of free radicals following this medication has prompted studies on the use of vitamin E (α-tocopherol), an antioxidant to treat patients suffering from such side-effects. The present study aimed at reproducing earlier encouraging results in treating 23 patients with vitamin E, using a double-blind crossover design. Inclusion criteria were: duration of tardive dyskinesia for at least 3 months, appearance of the symptoms during neuroleptic treatment or after stopping this kind of medication. The 10 subjects in the first group (Gl) were treated for 14 days with 1 200 mg vitamin E per day and then for 14 days with placebo. For the second group (G2) with 9 subjects, the treatment periods were inversed. The 2 dropouts in each group were not due to experimental problems: there was no complication due to vitamin E intake, or only negligible side-effects. Side-effects were rated on the AIM scale on days 0, 14 and 28. The results of the present study do not confirm earlier reports: there was no significant difference in the therapeutic effect between placebo and vitamin E in any of the groups. However, the fact of taking these symptoms into account in the physician-patient relationship has contributed significantly to a decrease of tardive dyskinesia in both groups, from the beginning until the end of the investigation period, during which both neuroleptic and tranquilizing treatments were kept constant. Further studies should include longer treatment periods with vitamin E or even test the preventive effect of vitamin E in the production of tardive dyskinesia by neuroleptics.