The treatment of tardive dyskinesia with baclofen.

Thirty-one psychiatric outpatients with tardive dyskinesia (TD) on neuroleptic medication were followed in a double-blind, randomized trial comparing baclofen (30-90 mg per day) to placebo. A repeated measures analysis of variance revealed no statistical difference between the baclofen-treated group and the placebo group for the total Abnormal Involuntary Movement Scale (AIMS) scores. There was a trend (P = 0.09) for an initial improvement, then a worsening of frequency counts across four visits. The authors attempt to explain this finding on the basis of information obtained from animal research.