Road safety

Drug-impaired driving

If you're affected by cannabis or other drugs, your ability to drive safely is compromised. 

If you're going to consume cannabis, the safe thing to do is to stay home or arrange alternative transportation, just like you do when you drink alcohol.​​


​Cannabis impairs both your ​​​cognitive and motor abilities, slows​​ your reaction time and ability to make decisions, and makes​ it harder for you to split your attention. These are crucial skills on the road. Researchers estimate that driving within three hours of consuming cannabis doubles your risk of having a crash.

Other drugs

Don't forget that illicit drugs and other legal drugs, including prescribed or over-the-counter medicine, may also affect your ability to drive. If you are taking any medication, check with your physician or pharmacist to understand how it may affect you and your ability to drive.

Combining drugs and alcohol can also greatly increase your risk of a crash, so if you're taking medication, make sure you aren't taking it with alcohol.​​

When is it safe and legal ​to drive if you have consumed cannabis?

The effects of cannabis vary depending on how often you consume cannabis, how much you've taken, how you've consumed it (smoking vs. eating), your physical and mental state at the time of consumption and other factors. 

​Cannabis ingested in the form of edibles is slower to take effect, but the effect can last much longer and be more intense than smoking it.

If you are learning to drive or at the novice level (L or N), you are restricted from having any amount of certain drugs in your system, including THC, while driving.

The cost of impaired driving

If you are charged with impaired driving, by either drugs or alcohol or both, you'll face a variety of penalties that could include fines, Driver Risk Premium and Driver Penalty Points on your licence, having your driver's licence seized, or being prohibited from driving.

Tips to get home safely​​

  • Take a taxi or ride-hailing service. Leave your car at home or parked overnight and pick it up the next day.

  • Take transit. Plan your routes before you go so you know how to get home safely.

  • Call a friend or take turns being the designated driver.

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