This paper presents some results of a German study of 57 road users in whose blood alcohol, drugs or medication were detected. The 18 cannabis takers were found to drive very fast at night, often made operating errors, and were sometimes involved in accidents on curves. Possible contributing factors were: (1) elated mood; (2) uncritical attitude to reactions; (3) attention disorders; (4) increased reaction time; (5) impairment of visual functions. However, they had often become passive and apathetic by the time that they were observed. The 15 drivers who had taken opiates and substitute drugs showed no conspicuous fast driving, but sometimes showed abrupt changes of speed with unmotivated braking and acceleration. The results show that specific driving characteristics, as well as psychophysical characteristics, must be considered when assessing the driving ability of drug consumers.
Samenvatting