This paper summarises a comprehensive review of benzodiazepines in relation to driving performance, recently published by the authors. The following aspects of work on this subject are considered: (1) application of theoretical pharmacological knowledge to the effects of benzodiazepines on the psychological requirements of road traffic; (2) epidemiological studies of accident frequency and the frequency of drug use by drivers; (3) experimental studies; (4) possibilities of applying the available knowledge to prevent accidents; (5) determining further research requirements. Most epidemiological studies suggest that people who take benzodiazepines tend to be over-represented among crash victims, but the causes of any such over-representation are not yet clear. Experimental studies have, for example, measured the effects of benzodiazepines on: (1) critical flicker fusion; (2) digit or symbol substitution test; (3) reaction times; (4) tracking tasks; (5) vehicle manoeuvres; (6) closed-circuit driving; (7) on-the-road driving performance. Some impairment of functions was found often, improved performance was found occasionally, but the vast majority of studies had inconclusive results. The newer benzodiazepines seem to have fewer behavioural side effects than the older ones.
Abstract