Effects of minor tranquilizers and antidepressants on psychomotor performance.

Results of laboratory and epidemiologic studies have raised concern that psychotropic drugs may contribute to accidents. This article reviews studies of the effects of minor tranquilizer and antidepressant drugs on psychomotor performance. Data clearly demonstrate that the most commonly prescribed tranquilizer, diazepam, impairs many aspects of psychomotor performance for several hours after dosing, and there is no evidence that behavioral tolerance develops with continued drug use or that patients are differently affected than nonpatients. Lorazepam similarly impairs psychomotor performance. Other frequently prescribed benzodiazepine drugs have not been sufficiently examined to warrant conclusions about their psychomotor effects. A newly marketed nonbenzodiazepine anxiolytic, buspirone, has been shown to have few effects on performance skills. Only one antidepressant, amitriptyline, has been studied thoroughly enough to conclude that it impairs psychomotor performance. The few studies of other, newer antidepressants suggest they may cause less impairment; however, more research is needed to confirm this.