Because of the efficacy of specific gamma-aminobutyric acid (GABA)
agonists in tardive dyskinesia, the authors tested the benzodiazepine
clonazepam in a 12-week, double-blind, placebo-controlled, randomized
crossover trial in 19 chronically ill patients with tardive dyskinesia who
were being treated with neuroleptics. They found a 35% decrease in
dyskinesia ratings with clonazepam treatment. The six patients with
predominantly dystonic symptoms showed greater benefit than the 13 patients
with predominantly choreoathetoid dyskinesias. Tolerance developed to the
antidyskinetic effect of clonazepam in the five patients whose long-term
use of the drug was followed, but a 2-week clonazepam-free period
recaptured its antidyskinetic effect.Abstract Teaser