Cannabis (Marijuana)
Cannabis (also known as marijuana, weed, or pot) refers to products derived from the cannabis plant. Different names for cannabis products may be used to describe what part of the plant was used or how the product was processed. Cannabis can be smoked, inhaled as a vapour, added to food or drinks, used as a tincture, or taken in capsules.
Cannabis contains hundreds of chemical substances that can affect the way we feel and think. Two of the most studied chemicals in cannabis are THC (delta-9-tetrahydrocannabinol) and CBD (cannabidiol). Although it is legal and can be used for therapeutic purposes, cannabis can also create potential health risks.
There are numerous laws that regulate cannabis use in Ontario, including impaired driving laws and the Smoke-Free Ontario Act.
Health Effects
While there are some limitations to what we know about the health effects of cannabis, there are some well-documented risks, including:
- cognitive, psychomotor and memory impairments
- hallucinations and impaired perception
- impaired driving and injuries (including fatalities)
- mental health problems (including psychosis)
- dependence
- pulmonary/bronchial problems There are also specific health risks for people who are pregnant or breastfeeding.
Long term, frequent cannabis use also appears to be associated with a syndrome of cyclical vomiting, known as Cannabis Hypermesis Syndrome. The syndrome is characterized by abdominal pain that is relieved by hot showers or baths. Cessation of cannabis use appears to be the best treatment.There are also risks associated with accessing cannabis from unregulated sources where the quality and purity of the product cannot be guaranteed.
Reducing the Risks
Canada’s Lower-Risk Cannabis Use Guidelines can help to reduce harmful impacts on your health when using cannabis. Specific guidelines are available for youth as well. Some harm reduction suggestions include:
- Delay taking up cannabis use until later in life
- Identify and choose lower-risk cannabis products
- Don’t use synthetic cannabinoids
- Avoid smoking burnt cannabis—choose safer ways of using (e.g., vaporizers, edibles)
- If you smoke cannabis, avoid harmful smoking practices (e.g., inhaling deeply, breath holding)
- Limit how much and how often you use cannabis
- Don’t use and drive, or operate other machinery
- Avoid cannabis use altogether if you are at risk for mental health problems or are pregnant
- Avoid combining the risks identified above
Medical Use of Cannabis
Cannabis use has been found to have therapeutic or medicinal effects to improve symptoms for some health conditions. However, research is lacking or has not supported use for many conditions, and you should consult your health care provider if you are considering using cannabis to help manage a health condition.
Even if the cannabis is medical, individuals must follow existing laws: including those relating to impaired driving and the Smoke-Free Ontario Act. Read more about the medicinal uses of cannabis from Health Canada and the Canadian Centre on Substance Use and Addiction.
Cannabis Edibles
Cannabis edibles are products that you eat or drink that contain THC and/or CBD. They can come in many forms, such as baked goods, candies, dissolvable strips, and beverages. While they may look like common food or drink items, cannabis edibles are like other drugs and can affect the way we think, feel and act.
Edible cannabis can also affect you differently than when it is inhaled:
- You won’t feel the effects as quickly because your body absorbs it slower.
- TIP: expect to wait 30 minutes to 2 hours to “feel it”
- Can create more intense effects
- TIP: start with a lower amount and go slow!
Cannabis poisonings in Ontario are increasing, particularly with edibles, as they can be mistaken for non-THC foods. If there are children in your home, always ensure that cannabis edibles are stored properly and out of reach.
Cannabis and Youth
Young people are particularly vulnerable to risks associated with (even occasional) cannabis use because brain development continues into a person’s 20s. The effects of cannabis use during adolescence are well documented: leading to the development of Low-Risk Cannabis Use Guidelines for Youth specifically.
Some factors that have been shown to help protect young people from experiencing harms related with cannabis use include:
- Developing social and personal skills and being exposed to positive peer norms
- Having supportive teachers
- Talking with parents, parents’ opinions, and family rules
Resources for Parents
- Cannabis Talk Kit – how to talk with your teen
- Cannabis Addiction and Withdrawal (Parent Action Pack)
- What Parents/Guardians and Caregivers Need to Know (CAMH)