About one in three adult drivers ages 21 to 25 have driven under the influence of alcohol or drugs during the past year, according to a new report, released today by the Substance Abuse and Mental Health Services Administration (SAMHSA). These data also show that 16.6 percent of adult drivers ages 21 or older (30.7 million persons) reported driving while under the influence of alcohol or illicit drugs during the past year.

SAMHSA extracted the data from the National Surveys on Drug Use and Health, 2002 and 2003. The report, "Driving Under the Influence among Adult Drivers," estimates that among adult drivers ages 21 or older, 15.7 percent drove under the influence of alcohol, 4.3 percent drove under the influence of illicit drugs; and 3.0 percent drove under the combined influence of alcohol and drugs, during the past year.

The report found that older drivers are less likely than younger drivers to drive while under the influence of alcohol or illicit drugs. The data showed that 33.8 percent of drivers ages 21-25 had done so. In comparison, 24.3 percent of those ages 26-34 drove while under the influence of alcohol or illicit drugs and l8.5 percent of those ages 35 to 49 did so. Only 10 percent of those ages 50-64 drove under the influence of alcohol and illicit drugs in the past year, as did 3.4 percent of those ages 65 and older.

SAMHSA defines illicit drugs as marijuana, cocaine, inhalants, hallucinogens, heroin or non medical use of prescription drugs.

The data show 22 percent of male drivers ages 21 and older drove under the influence of alcohol or drugs, compared to 11.4 percent of females in 2002 and 2003.

The report is available on the web at http://oas.samhsa.gov. SAMHSA, a public health agency within the U.S. Department of Health and Human Services, is the lead federal agency for improving the quality and availability of substance abuse prevention, addiction treatment and mental health services in the United States.