Road Safety

Drug Impairment

Drug use can impair your ability to drive and increase the likelihood of a vehicle collision.

Driving while impaired by drugs, including prescription and non-prescription medications and illicit drugs, is illegal in Canada. Drivers found guilty of drug-impaired driving face the same penalties as those convicted of alcohol-impaired driving.

Drugs come in many forms and have a wide range of possible effects and side effects. Many people are under the mistaken impression that they are either unaffected or can drive better under the influence of drugs such as marijuana. This is simply not true.


It’s illegal to drive if you’re impaired by THC. Marijuana affects driver concentration and reaction time. Some people mistakenly believe they can drive well after using marijuana – in fact, it doubles the risk of a crash.

Prescription drugs

Tranquilizers, antidepressants, sleeping pills and similar drugs can negatively affect driving ability even if taken in the prescribed dosage. Sedatives and painkillers can slow reaction time, impair coordination and decrease attentiveness. If you drive while impaired by prescribed medication, you can be charged with impaired driving. Discuss the possible effects of any medication with your doctor or pharmacist. Learn more.

Other illegal drugs

Illicit drugs may cause hallucinations, hostility and aggressiveness in addition to dulling normal thought processes and impairing motor skills. Stimulants like cocaine can reduce coordination and increase risk-taking behaviour. Opioids can slow reaction time and reduce ability to concentrate. If you are found to be driving while under the influence of illegal drugs, you will be charged with impaired driving. Learn more about the effects of drugs.

Combining drugs and alcohol can amplify the effect of each substance, even in small quantities. If you mix drugs with alcohol, do not drive.

If you take any drugs, including marijuana or prescription medication, don’t drive. Plan ahead to get home safely.

Additional Resources

General information

The Canadian Centre on Substance Use and Addiction – Drug-Impaired Driving Toolkit

For teens

TADD Manitoba

RCMP: The Truth – Youth and Drug-Impaired Driving

For Parents

Drug Free Kids Canada