Consumer Information – Cannabis

The official version of this document, which has been incorporated by reference as part of the Cannabis Regulations, is the PDF version available for download at right. The document must be printed double-sided (one side English, one side French), in black and white, full size, on 8.5 by 11 inch white paper. Questions concerning the use of this document can be directed to:


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Organization: Health Canada

Date published: 2019-06-14

Cannabis contains substances that affect the brain and body, including THC and CBD. THC causes the intoxicating effects of cannabis. CBD is not intoxicating and may reduce some of the effects of THC; however, it does have an effect on the brain.

Everyone's response to cannabis differs and can vary from one time to the next. To minimize your risk or if you are a new consumer, look for a product containing 2.5 mg of THC or less or 10% THC (100 mg/g) or less, and an equal or higher amount of CBD.

Common immediate effects of THC

  • Euphoria ("high"); drowsiness; anxiety; impaired ability to remember, concentrate or react quickly.

Important notes about eating or drinking cannabis and consuming products with high THC

  • It can take up to 4 hours to feel the full effects from eating or drinking cannabis. Consuming more within this time period can result in adverse effects that may require medical attention.
  • The higher the THC content of a product, the more likely you are to experience adverse effects and greater levels of impairment.
  • Store all cannabis (particularly edible cannabis) securely and out of reach of children and pets.
  • If you or someone you know has accidently consumed cannabis or consumed too much cannabis and is not well, contact your local poison centre or seek medical attention.
Ways of using cannabis When effects could begin How long effects could last
Smoking/vaping Seconds to minutes Up to 6 hoursFootnote *
Eating/drinking/swallowing 30 minutes to 2 hours Up to 12 hoursFootnote *
Footnote 2

some effects could last as long as 24 hours

Return to footnote * referrer

What are some harms and how to lower the risks

  • Delay using cannabis to later in life. Teenagers and young adults are at greater risk of harms because the brain continues to develop until around the age of 25.
  • Don’t drive or operate heavy equipment after using cannabis. Cannabis can cause drowsiness and impair your ability to concentrate and make quick decisions.
  • Avoid frequent use. Frequent and prolonged use (daily or near-daily use across months or years) increases the risk of dependence and may bring on or worsen disorders related to anxiety and depression.
  • Avoid smoking cannabis. The smoke from cannabis contains the same harmful chemicals found in tobacco smoke.
  • Avoid combining cannabis with alcohol and/or other substances. Using cannabis at the same time as alcohol and/or other drugs can cause more severe levels of impairment and adverse effects.

Know the rules

  • It is your responsibility to know the rules and to follow them. To find out more about the rules for cannabis, visit


Talk to your health care practitioner if you have any questions or concerns regarding cannabis use and your health.

For questions or concerns about a product, or to report adverse reactions, contact the manufacturer. You can also report concerns, complaints or adverse reactions to Health Canada.

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