Effect of baclofen on tardive dyskinesia.
Eighteen chronic psychiatric patients with neuroleptic-induced tardive dyskinesia of 1/2-9 years duration participated in a double-blind crossover study on the effect and side effects of baclofen and placebo in the treatment of tardive dyskinesia. Each treatment phase lasted 3 weeks. Evaluation of the results included an assessment of video-tape recording. Baclofen (20-120 mg daily) reduced the hyperkinesias (median score from 5 to 3, P less than 0.05) and increased the parkinsonism (median score from 5 to 7, P less than 0.01). The effect on the oral movement pattern of tardive dyskinesia was characterized by a reduced frequency, an unchanged or slightly reduced amplitude, and an increased duration of each separate mouth opening and tongue protrusion, a response pattern very similar to the response pattern of alpha-methyl-p-tyrosine, an inhibitor of the catecholamine synthesis. Sediation, muscular weakness, and confusion were observed in 50% of the patients. These side effects, appearing mainly in elderly patients, sometimes set in before the anti-hyperkinetic effect, thus limiting the practical usefulness of baclofen in the treatment of tardive dyskinesia.
D000368:Aged; D000613:Aminobutyrates / Q000627:therapeutic use*; D001418:Baclofen / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D002986:Clinical Trials as Topic; D004311:Double-Blind Method; D004409:Dyskinesia, Drug-Induced / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010919:Placebos
D000613:Aminobutyrates; D010919:Placebos; D001418:Baclofen