Key points
- Driving under the influence (DUI) laws are not just for alcohol. Driving under the influence of drugs, including cannabis, is also dangerous and illegal.
- Driving is a complex task that requires your full attention to stay safe and alert.
What you need to know about cannabis use and driving
Cannabis affects areas of the brain that control your body's movements, balance, coordination, memory, and judgment.12 Cannabis use can impair important skills required for safe driving by:12
- slowing your reaction time and ability to make decisions,
- impairing coordination, and
- distorting perception.
Studies have shown an association between acute cannabis use and car crashes, but more research is needed.12 It is difficult to connect the presence of cannabis or concentration of tetrahydrocannabinol (THC), the compound responsible for cannabis'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 cannabis and alcohol) at the same time can increase impairment.3
Fast facts
- Cannabis is the most commonly used drug that is illegal at the federal level in the United States. 4
- In 2021, an estimated 52.5 million people used cannabis in the past year.5
- After alcohol, cannabis is the substance most often associated with impaired driving.6
- In 2017, about 1 in 8 high school drivers reported driving after using cannabis at least once during the past month.4
What you can do to prevent impaired driving
If you intend to drive, the safest option is not to use any alcohol or drugs, including cannabis. 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 cannabis:
- 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.
- National Academies of Sciences, Engineering, and Medicine. The health effects of cannabis and cannabinoids: the current state of evidence and recommendations for research. Washington, DC: The National Academies Press; 2017. https://nap.nationalacademies.org/catalog/24625/the-health-effects-of-cannabis-and-cannabinoids-the-current-state. Accessed February 8, 2024.
- Compton R. Marijuana-impaired driving. A report to Congress. Washington, DC: National Highway Traffics Safety Administration, 2017. https://www.nhtsa.gov/sites/nhtsa.dot.gov/files/documents/812440-marijuana-impaired-driving-report-tocongress.pdf.
- Lacey JH, Kelley-Baker T, Berning A, et al. Drug and alcohol crash risk: A case-control study (Report No. DOT HS 812 355). Washington, DC: National Highway Traffic Safety Administration; 2016.
- Li L, Hu G, Schwebel DC, et al. Analysis of US teen driving after using marijuana, 2017. JAMA Netw Open. 2020 Dec 1;3(12):e2030473. Doi: 10.1001/jamanetworkopen.2020.30473.
- Substance Abuse and Mental Health Services Administration. Key substance use and mental health indicators in the United States: Results from the 2021 National Survey on Drug Use and Health (HHS Publication No. PEP22-07-01-005, NSDUH Series H-57). Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration. 2022. https://www.samhsa.gov/data/report/2021-nsduh-annual-national-report. Accessed February 9, 2024.
- Azofeifa A, Rexach-Guzmán BD, Hagemeyer AN, et al. 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. Doi: 10.15585/mmwr.mm6850a1.