Alcohol has long been associated with injury, but the relationship between other drugs and injury is less clear. Blood samples from 894 patients presenting to two Emergency Departments for treatment of motor vehicle injury sustained in passenger cars, station wagons, vans and pickup trucks, were tested for alcohol and other drugs. Results were related to demographic characteristics, including prior history of alcohol and drug use; crash characteristics; and injury characteristics. Alcohol was associated with more severe crashes, but other drugs, in the absence of alcohol, were not. The crashes involving drugs but no alcohol were very similar to those involving neither alcohol nor drugs.