The present study was designed to investigate the efficacy of clonazepam in neuroleptic-induced akathisia. Twelve patients were treated during 2 weeks with clonazepam or placebo in a double-blind randomized design. Akathisia was scored by an independent rater before and after treatment, as well as 1 week after medication withdrawal. Clonazepam (0.5–2.5 mg/day) induced a significantly higher reduction in the akathisia scores than placebo (p < 0.05). One week after stopping the drug, there was a partial but significant relapse in the treated group as compared with controls, in whom the symptoms remained stable. In addition, the clinical improvement was significantly correlated with the daily dose of clonazepam (rs= 0.827; p < 0.002). These results support the potential usefulness of clonazepam in the treatment of neurolepticinduced akathisia and suggest an optimal daily dose in the range of 10–40 μg/kg.