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Drug-Impaired Driving

Understanding How Marijuana Affects Driving

NHTSA, Ad Council Launch Drug-Impaired Driving Campaign

You’ve helped change the perception of drunk driving by making the phrase “Friends Don’t Let Friends Drive Drunk” common, and now it’s time to spread the message about the dangers of using marijuana and driving. 

NHTSA has teamed up with the Ad Council to launch the drug-impaired-driving prevention campaign, If You Feel Different, You Drive Different. Together, we hope to change the cultural conversation around driving after using marijuana, to make it as socially unacceptable as driving drunk. 

Though 33 states have changed their laws regarding marijuana, it’s still illegal everywhere to drive impaired by the drug. According to studies, marijuana can slow your reaction time, impair judgment of distance, and decrease coordination, which are essential when you’re behind the wheel of a vehicle. 

In recent years, drug-impaired driving has become a major highway safety issue. According to a NHTSA study, from 2007-2013 there was a 48% increase in weekend nighttime drivers who tested positive for tetrahydrocannabinol (THC)—the chemical responsible for marijuana’s psychological effects. 

If you’ve used marijuana, or any other impairing substance, don’t get behind the wheel. Instead, here are some tips for getting home safely.

  • Pass the keys to a sober driver who can safely drive you to your final destination. It is never okay to drive while impaired by any substance.
  • Take the keys away from a friend who is about to drive while impaired by drugs, and arrange to get them home safely. Don’t worry about offending someone—they’ll thank you later.

As part of the campaign, NHTSA and the Ad Council have launched The site is a resource to help people make smart decisions about driving, and to remind them about the dangers and illegal nature of drug-impaired driving.