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OMA blog
Oct. 29, 2019

Recreational Cannabis

Canada is one of two countries in the world to formally legalize the cultivation, possession and consumption of recreational cannabis. On October 17th, the final piece of Canada’s cannabis regulations comes into force and with it, recreational cannabis extracts, topicals and edibles will become legal. 

Just like alcohol, there are risks to consuming cannabis. Those who choose to partake should know the possible risks and how to consume it responsibly.


A concern for doctors is the specific danger posed by edibles. We recognize that the health effects of cannabis are an emerging field that needs greater research.

When people smoke or vape cannabis, the "high" comes on almost right away, and generally lasts 2-3 hours. With edibles, it can take significantly longer for any effects to be felt, and the effects last much longer.

Users can wrongly mistake this slow onset to mean that they have not consumed enough, and so they consume more. This is called "dose stacking", and it can be very dangerous. It can cause extreme intoxication, as well as anxiety, and the effects can last up to 12 hours.

Accidental ingestion is also a concern with edibles. Edibles can look like regular snacks and can be easily consumed accidentally. Users should take precautions to always safely store edibles and especially keep them out of reach of children and pets.

Mental health and addictions concerns

Just as concerning as the physical concerns are the potential mental health and addictions concerns posed by recreational cannabis. New evidence has shown that the use of high-concentration THC (the psychoactive compound in cannabis) is associated with an increased risk of psychosis and psychotic disorders.

Cannabis can be addictive, especially for teenagers. The addiction risk is one in six for those who start using as a teen.

Understanding the risks

It is important that those who are using, or plan to use cannabis recreationally, understand the risks of doing so. To support doctors in informing patients, the OMA has created a cannabis resource centre, where doctors can access up-to-date tools and information on this topic.

Public education is essential to reduce potential harm as edibles become legal. In fact, in addition to this blog post, Ontario’s doctors are releasing two podcasts that focus on edibles and responsible consumption to help get information on this important topic.

Doctors rely on science and evidence, and research shows us that there are specific dangers associated with cannabis, and those dangers can be serious. We have an obligation to ensure that recreational cannabis is consumed responsibly and safely.  If you have any questions about recreational cannabis, please speak with your doctor. Because for information on all health issues, there is no substitute for a doctor.

dr sohail gandhi Dr. Sohail Gandhi, OMA President