SOME ASPECTS OF THE EFFECTS OF CLOBAZAM ON HUMAN PSYCHOMOTOR PERFORMANCE

1 Three studies are described, the first being a comparison of the effects of acute night‐time doses of clobazam 20 mg, amylobarbitone sodium 100 mg, nitrazepam 5 mg and placebo, on choice reaction time, critical flicker fusion (CFF) and stabilometer performance. Clobazam improved early morning performance on a choice reaction test, in contrast to the other two active drugs. 2 Repeated doses of clobazam 10 mg three times daily, chlordiazepoxide 10 mg three times daily and diazepam 5 mg three times daily were given for 5 days. Again clobazam did not produce any impairment of psychomotor performance, and noticeably increased CFF thresholds. 3 The effects of an acute night‐ time dose of clobazam 20 mg on psychomotor performance the morning after night‐time medication were correlated with the neuroticism scores (on the EPI) of the subjects. Clobazam exerts a differential effect on psychomotor performance dependent on the basic personality trait. 4 Clobazam seems to differ significantly from the 1,4‐benzodiazepines in that, although it reduces anxiety, it does so without any apparent impairment of psychomotor performance. 1979 The British Pharmacological Society