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Cannabis (Marijuana)

What is cannabis?

Cannabis, also known as marijuana, is a drug that is made up of the leaves, flowers, and buds of the hemp plant Cannabis sativa. It is often smoked in pipes or hand-rolled cigarettes. But it can also be vaporized, applied to the skin, cooked in food or beverages, or brewed into tea.

Health risks

  • Regular use of cannabis may affect brain development.  Minimize use to age 25 to reduce risk of these lasting consequences.

  • Smoking cannabis regularly can increase risk of respiratory tract irritation, leading to chronic coughing, shortness of breath and wheezing. 

  • Cannabis may worsen symptoms of depression or anxiety and may also cause symptoms such as

    • panic attacks

    • paranoia

    • hallucinations

  • It may also trigger the onset of schizophrenia in those already vulnerable. 

  • Those who use cannabis frequently over a period of time may be putting themselves at risk of addiction or dependence.  The risk is higher for those who start to use cannabis regularly at an early age. Addicted or dependent users typically require more cannabis over time in order to feel the same 'high'.  They may also develop withdrawal effects when they stop using (such as nausea, irritability, depression, insomnia, and cravings for cannabis).  If you feel that you may be addicted or dependent, talk to your doctor.

Safety tips

  • Avoid driving or engaging in other potentially dangerous activities (3 hours after inhaling or 6 hours after ingesting) after consuming as cannabis may impair coordination and reaction time.

  • Cannabis should be kept out of reach of infants, children and pets to avoid accidental poisonings

  • Avoid  cannabis if you are pregnant, planning to become pregnant, or breastfeeding

  • Products currently available at dispensaries have been produced without regulatory oversight for quality and safety

  • Edible products in the form of candy or baked goods are associated with accidental poisoning among young children, and should be kept in child proof containers

Minimize your risk

  • Start with small amounts:  It's better to use only as much cannabis as is necessary to achieve desired effects.  With inhaled cannabis, start with one or two small puffs; with edible cannabis products, start with a small bite.

  • Wait to feel the full effects:  Dosage can make a big difference between getting the desired effects and feeling uncomfortable or anxious.  Wait at least 10 minutes to feel the effect of inhaled cannabis and at least one hour to feel the effects of edible cannabis products. It's easier to control the dose when inhaling cannabis versus eating it; most acute hospital visits from cannabis use are from those who get sick from eating cannabis edibles.

  • Do not mix cannabis with alcohol or other drugs, as this can increase impairment. Negative effects of cannabis may be exacerbated when used with alcohol, resulting in symptoms such as anxiety, dizziness, sweating, nausea and vomiting. 

  • If you have had too much cannabis, try to remain calm, stay hydrated, and eat something.  Stay with friends in a safe place.  The effects will wear off. 

  • If smoking, take shallow inhales and exhale right away. It only takes a few seconds for your lungs to absorb cannabis; deep inhalation and breath holding may lead to pain and breathing troubles. Vaporizing may cause less lung irritation than smoking.

Substance use services

If you're struggling with substance use or addiction, talk to your doctor, and/or access our free services.

VCH substance use services


Individual, family, and small group counselling is available to people of all ages who are directly or indirectly affected by alcohol and other drug use by calling the 24-hour BC Alcohol and Drug Information and Referral Service in the Lower Mainland at (604) 660-9382 or toll-free anywhere in B.C. at 1 (800) 663-1441.

Adult resources

"Take Care with Cannabis" – Harm reduction resource created by VCH and CARBC
Here to Help –  Cannabis info sheet from CARBC 

Youth resources

"Take Care with Cannabis" – harm reduction resource created by VCH and CARBC
Cannabis Info Page – Kelty Mental Health Resource Centre

Teachers/Parents resources

Cannabis and Youth, a parent's guide – CARBC
Substance use resources for youth and parents – SACY
Marijuana Use Data from 2013 Adolescent Health Survey – McCreary Centre Society, 2013
Blunt Talk: Harms Associated with Early and Frequent Marijuana Use Among BC Youth – McCreary Centre Society, 2016

SOURCE: Cannabis (Marijuana) ( )
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