Effects of alcohol on buspirone and lorazepam actions.

Psychomotor and psychologic effects of single doses of buspirone (10 and 20 mg) and lorazepam (2.5 mg) alone or combined with alcohol (1 gm/kg) were investigated in 12 healthy young men (crossover study). Lorazepam alone impaired psychomotor skills (tracking, body balance, extraocular muscle balance, and flicker recognition), the effects being maximal at 180 min. This impairment was not subjectively perceived by the subjects. Neither dose of buspirone alone impaired objective measurements, although buspirone, especially in the 20-mg dose, was felt to cause drowsiness, weakness, and faintness. Lorazepam, but not buspirone, interacted with alcohol.