Placebo-controlled study on acute and subchronic effects of buspirone vs bromazepam utilizing psychomotor and cognitive assessments in healthy volunteers.

The acute and subchronic effects of orally administered buspirone (acute: 15 mg; subchronic: 5 mg t.i.d.; Day 7:5 mg) and bromazepam (acute: 6 mg; subchronic: 2 mg t.i.d.; Day 7: 2 mg) on psychomotor and cognitive parameters were explored vs placebo in a randomized, double-blind crossover design with three periods in 12 healthy male volunteers. The washout periods between active treatments lasted one week. Psychomotor and cognitive measurements were taken with the Oculodynamic Text (ODT), which is a computerized psychophysiological online testing device for the simultaneous measurement of electrooculographic and performance (signal identification) parameters. Subjective side effects were recorded with a symptom checklist (41 items) with regard to the first and seventh day of administration. Intradiurnal assessments were done at 0, +1, +3, and +5 hours post-dose on Days 1 and 7 of each of the three randomized treatment periods. Buspirone behaved placebo-like in the EOG and signal-identification parameters after acute and subchronic administration. After bromazepam the respective parameters were significantly impaired--acutely as well as subchronically. Acute and subchronic buspirone was significantly superior to bromazepam with regard to the majority of psychophysiological parameters. The incidence of acute side effects was higher for both active treatments than for placebo. With buspirone there were fewer acute and subchronic side effects than with bromazepam. The side effect profiles of the three preparations were different. With regard to all active treatments the incidence of side effects was lower on Day 7 after the subchronic dosing period--with a third of the subchronic dose--than after the first single administration.