Cannabis Facts November 2019: Self-Medicating with Cannabis: A complex and concerning issue

Self-Medicating with Cannabis: A complex and concerning issue

November 2019

People who choose to use cannabis may do so for a variety of reasons. When people use cannabis to cope with mental health problems or to relieve symptoms associated with other medical conditions without a medical document from a healthcare professional – this is referred to as self-medication.

Some of the more common reasons for self-medication with cannabis include chronic pain, anxiety, depression, and sleep problems.1,2 A study of Canadian youth revealed that many youth used cannabis as a coping strategy, and that many youth thought cannabis could relieve a variety of conditions (including anxiety, depression, and stress) whether prescribed by a doctor or through self-medication.3

Local data from our cannabis survey showed that the majority (64%) of people who were using cannabis for medical purposes did not have a document from a healthcare professional and were therefore self-medicating.

While some people may experience benefits, self-medicating with cannabis is a complex issue and it is important to discuss some of the key concerns:

  • Cannabis is a complex substance. Cannabis has over 100 cannabinoid chemicals, each with different effects and different interactions between other cannabinoids and substances in cannabis. Different cannabis products contain different levels of these cannabinoids (the most commonly studied are THC and CBD), and the amount of each cannabinoid consumed and the way it is consumed (e.g., smoked, vaped, eaten, applied on skin) produces different effects.4 Self-medicating with “cannabis” can therefore be complicated and difficult to determine the dosage.
  • The evidence for therapeutic benefit is limited. Although many people report using cannabis to manage a large variety of medical conditions, including mental health problems, there is actually not strong clinical evidence to support a benefit for many of these conditions.5 Currently, there is strong or moderate evidence that cannabis or certain cannabinoids can help with chronic pain among adults, chemotherapy-induced nausea and vomiting, spasticity related to multiple sclerosis, and short-term sleep outcomes in patients with certain conditions.6 More recent research has also shown promise for CBD in reducing epileptic seizures.7 Although research is still evolving in this area, it is important to look at current evidence.
  • People who use cannabis as a coping strategy for mental health problems can have worse outcomes. While some people do report that cannabis can temporarily reduce stress, anxiety and depression, using cannabis as a coping mechanism can make mental health problems worse in the long-term and increases the risk for developing cannabis addiction.8,9,10,11,12  More research is still needed to determine the potential effects of specific cannabinoids (like CBD) on mental health outcomes.12
  • There are known harms to using cannabis. Regular cannabis use can lead to addiction, mental health problems, and can harm learning and memory. These risks are higher for people who start using cannabis at a young age, who use frequently, and who use products with high levels of THC.10 In addition, smoking cannabis can cause harm to the lungs, and people who self-medicate with cannabis report higher rates of smoking than those who use cannabis with medical guidance and documentation.13
  • Many people who use for medical reasons also use for non-medical reasons. Non-medical use of cannabis is common among people who use cannabis for medical reasons.1,14 Although more research is needed to understand this relationship, one study expressed concern about numerous youth who began using cannabis to self-medicate and then went on to use “recreationally.”3
  • Cannabis may interact with medications, medical conditions or may not be the best treatment option. It is important to talk to a healthcare provider when considering cannabis for medical reasons. Cannabis can interact with certain medications and is not advisable for people with certain medical conditions.15 In addition, cannabis or cannabinoids may not be the best treatment option. Even for medical conditions where cannabis or cannabinoids are supported by strong evidence, they are not considered to be first-line treatment options.5 Moreover, managing symptoms without the guidance of a medical professional may lead to undiagnosed health problems which could lead to greater harm.

Actions that WDGPH is taking

WDGPH’s “Talking About Weed” website provides information to youth and adults about the importance of speaking to a healthcare provider when considering cannabis for medical reasons, and links to appropriate resources. Information is also available on the health effects of cannabis use to help people make informed decisions. In addition, WDGPH participated with other health units on a consultation about the potential market for cannabis health products without medical oversight, where we expressed concerns around youth access, product types, and self-medicating.


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  4. Canadian Public Health Association. Cannabasics Fact Sheets [Internet]. 2018 [cited 2019 Oct 24]. Available from:
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  11. Moitra E, Christopher P, Anderson B, Stein M. Coping-motivated marijuana use correlates with DSM-5 cannabis use disorder and psychological distress among emerging adults. Psychol. Addict. Behav, 2015; 29(3): 627-632.
  12. Botsford S, Yang S, George T. Cannabis and cannabinoids in mood and anxiety disorders: Impact on illness onset and course, and assessment of therapeutic potential. Am J Addict, 2019; 000:1-18.
  13. Statistics Canada. National Cannabis Survey, fourth quarter 2018 [Internet]. 2019 Feb 7 [cited 2019 Oct 24]. Available from:
  14. Statistics Canada. National Cannabis Survey, second quarter 2019 [Internet]. 2019 Aug 15 [cited 2019 Oct 24]. Available from:
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