Driving Under the Influence of Marijuana, Alcohol, and Both

How common is driving under the influence of marijuana? Of driving under the influence of alcohol? Of driving under the influence of both at the same time?

The Analysis

To find out, self-reports of drivers age 16 to 25 were analyzed. The data came from the National Survey on Drug Use and Health from 2002 through 2014. That survey is conducted by the U.S. Substance Abuse and Mental Health Services Administration (SAMSHA).

The incidence of driving under the influence of alcohol alone dropped 59% among those age 16-20. It fell 38% among those age 21-25.

influence of marijuana

Driving under influence of marijuana and alcohol at same time greatly increases risk of crash.

Driving under the influence of both alcohol and marijuana dropped 39% among those age 16-20. It declined 52% among those age 21-25.

The prevalence of driving under the influence of marijuana alone fell 18%, but only among drivers age 16-20.

Between 2002 and 2014, the incidence of driving under the influence of alcohol, marijuana, and both generally dropped greatly.

The effects of alcohol and marijuana on driving skills is additive. Together, they have much greater effect than separately. This suggests the need for greater concern about reducing driving while under the influence of both at the same time.

Source

Azofeila, A., et al. Driving under the influence of alcohol, marijuana,  and alcohol and marijuana combined among persons aged 16-25 years  – United States, 2002-2014. Morbidity and Mortality: Weekly Report, 2015, 64(48), 1325-1329.

Resources

Beddard, M., et al. The impact of cannabis on driving.  Canad J Pub Health, 2007, 98(1),  6-11.

Hanson, D. The Effects of Substances on Driving. In: Miller, Peter (Ed). Principles of Addiction: Comprehensive Addictive Behaviors and Disorders. Amsterdam, The Netherlands: Elsevier Academic Press, 2013.

Ramaekers, J., et al. Marijuana, alcohol and actual driving performance.  Hum. Psychopharm. Clin. Exp., 2000, 15, 551-558.

Schwilke, E., et al.  Changing Patterns of Drug and Alcohol Use in Fatally Injured Drivers in Washington State.  J Foren Sci, 2006, 51(5), 1191-1198.

Sewell. R., et al.  The Effect of Cannabis Compared with Alcohol on Driving.  Am J Addict., 2009, 18(3),  185-193.