Fast Facts
  • Marijuana is the most commonly used drug that is illegal at the federal level in the United States, with an estimated 48.2 million people using it at least once in the past year in 2019.4
  • After alcohol, marijuana is the substance most often associated with impaired driving.5
  • In 2017, about 1 in 8 high school drivers reported driving after using marijuana at last once during the past month.6

1-800-CDC-INFO (232-4636) www.cdc.gov

What You Need To Know About Marijuana Use and Driving

Driving under the influence (DUI) laws are not just for alcohol. Driving under the influence of drugs, including marijuana, is also dangerous and illegal. Driving is a complex task that requires your full attention to stay safe and alert. Marijuana affects areas of the brain that control your body’s movements, balance, coordination, memory, and judgment.1,2 Marijuana use can impair important skills required for safe driving by:

  • slowing your reaction time and ability to make decisions,
  • impairing coordination, and
  • distorting perception.1,2

Studies have shown an association between acute marijuana use and car crashes, but more research is needed.1,2 It is difficult to connect the presence of marijuana or concentration of tetrahydrocannabinol (THC), the compound responsible for marijuana’s psychoactive properties (the “high”), to impairment in driving performance for an individual person.2 Studies have shown that the use of multiple substances (such as marijuana and alcohol) at the same time can increase impairment.3

What you can do to help prevent impaired driving

If you intend to drive, the safest option is not to use any alcohol or drugs, including marijuana. Here are steps you can take to help prevent impaired driving if you plan to use, are using, or have used alcohol or drugs, including marijuana:

  • Choose not to drive and remind your friends and family to do the same.
  • Assign a trusted designated driver who will not drink or use drugs when you are going out with a group of people you know.
  • Plan on getting a ride home from someone who has not been drinking alcohol and/or using drugs, using a rideshare service, or calling a taxi.
  1. National Academies of Sciences Engineering and Medicine, “The health effects of cannabis and cannabinoids: Current state of evidence and recommendations for research,” Washington, DC, 2017.
  2. Compton R. (2017, July). Marijuana-Impaired Driving – A Report to Congress. (DOT HS 812 440). Washington, DC: National Highway Traffic Safety Administration.
  3. Lacey JH, Kelley-Baker T, Berning A, Romano E, Ramirez A, Yao J, & Compton R. (2016, December). Drug and alcohol crash risk: A case-control study (Report No. DOT HS 812 355). Washington, DC: National Highway Traffic Safety Administration.
  4. Substance Abuse and Mental Health Services Administration. (2020). Key substance use and mental health indicators in the United States: Results from the 2019 National Survey on Drug Use and Health (HHS Publication No. PEP20-07-01-001, NSDUH Series H-55). Rockville, MD: Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration. Retrieved from https://www.samhsa.gov/data/
  5. Azofeifa A, Rexach-Guzmán BD, Hagemeyer AN, Rudd RA, Sauber-Schatz EK. Driving Under the Influence of Marijuana and Illicit Drugs Among Persons Aged ≥16 Years — United States, 2018. MMWR Morb Mortal Wkly Rep 2019;68:1153–1157.
  6. Li L, Hu G, Schwebel DC, Zhu M. Analysis of US Teen Driving After Using Marijuana, 2017. JAMA Netw Open. 2020 Dec 1;3(12):e2030473.