The influence of cannabis and alcohol on driving

The results from a study of the influence of different doses of cannabis and alcohol on driving and driving related skills are reported. Male drivers who were regular cannabis and alcohol users undertook a variety of different tasks. The participants were given cannabis to smoke in the form of a prepared grass-based cannabis cigarette and had a drink that may or may not have contained alcohol. The prepared 'grass' based cannabis cigarettes varied in active THC (tetrahydrocannabinol) content to give a placebo, and a low dose. The drinks were either a placebo or about 10% by volume of alcohol. The participants drove the TRL driving simulator in a variety of scenarios and various measures of their driving skill were assessed. They also took an adaptive tracking task. They underwent sobriety testing 10-15 minutes after dosing and completed a mood questionnaire at different times during their test session. (A)