During a recent 5-month period, 201 injured drivers were admitted to a level 1 trauma center. Blood alcohol concentrations (BACs) and drug screens were obtained in 187 and 164 subjects, respectively. BACs were positive in 37% and other drugs were confirmed in 40%, suggesting that alcohol and drug use among injured drivers is comparable. More than half of the drivers using alcohol also had drugs detected on the screening examination. Other investigators have previously established driving impairments associated with some of these drugs. These results indicate that the drug problem on our highways may be greater than previously recognized.