The reversibility of "permanent" tardive dyskinesia.

Neuroleptic-induced tardive dyskinesia (TD) that persists for 1 year or more following withdrawal of neuroleptics is usually said to be permanent. Early spontaneous remissions have been well described but most such remissions occurred within the first few months following neuroleptic withdrawal, and no published studies have followed patients for more than 2 years to evaluate permanence of remission. Over the last 12 years, we studied six patients with TD who, on prolonged follow-up, were found to have complete remission of their abnormal movements after a neuroleptic-free period of more than 2 years (2 1/2-5 years). All six patients were 61 years old or younger when their TD was diagnosed and their neuroleptics withdrawn. In five of the patients, remission occurred while the patients were not taking medication for the movements, while one patient had been on long-term, high-dose (2 mg/day) reserpine therapy for more than 3 years. The incidence of late remission of TD is not known and cannot be estimated from these selected patients, but these cases demonstrate that persistence of abnormal movements of TD for 2 or more years following neuroleptic withdrawal does not imply permanence in all patients. We suggest that TD be considered a persistent rather than an invariably permanent disorder.