Levetiracetam in tardive dyskinesia: an open label study.

Levetiracetam (LEV), a novel antiepileptic drug, has demonstrated antidyskinetic effect in preclinical animal models of Parkinson's disease (PD) and in one open label study in PD patients with levodopa-induced dyskinesia. The acute antidyskinetic effects of LEV in patients with tardive dyskinesia were evaluated in an open label study. Eight patients received oral LEV (1,000 mg/day) for 1 month and blinded evaluations were performed at baseline and at the end of the treatment period. A significant reduction of the abnormal movements was recorded while psychiatric symptoms did not worsen and the adverse event profile was benign. LEV may be efficacious for the treatment of tardive dyskinesia and deserves further clinical testing.