Cannabis and Alcohol: Effects on Simulated Car Driving

Abstract
The effects of cannabis and alcohol on simulated car driving were studied. Cannabis resin containing 4 percent Δ1-tetrahydrocannabinol was administered orally in three doses equivalent to 8, 12, and 16 milligrams of that component. Alcohol was given orally in one standard dose of 70 grams. Both cannabis and alcohol increased the time required to brake and start, whereas alcohol increased while cannabis decreased the number of gear changes. An effect of dosage on response was observed with cannabis.