Last updated October 23, 2026 | Published on June 20, 2022
People consume cannabis for many different reasons and to varying degrees. Understanding how cannabis use can change over time, recognizing the signs of cannabis use disorder and knowing where to find support can help you make informed decisions about your consumption.
Note: this information does not replace professional screening for or treatment of cannabis use disorder.
What is cannabis use disorder?
Cannabis use disorder (CUD) is defined in the American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (commonly called the DSM-5) as “a problematic pattern of cannabis use leading to clinically significant impairment or distress.” In plain terms, that means being unable to stop consuming cannabis despite experiencing severe consequences.
While most people consume cannabis without developing a problematic use, others may find that their consumption begins to interfere with their health, relationships, work or daily responsibilities.
Symptoms of cannabis use disorder
To better understand cannabis use disorder, medical experts often refer to the four C's:
- craving the substance
- the compulsion to use it
- loss of control of the amount or frequency of use
- use despite the consequences
You may find yourself needing to consume more to get the same desired effects, needing to use cannabis before doing certain activities, missing work or driving while impaired. You may also notice an impact on your relationships, such as experiencing conflict with family or friends.
9% of people who consume cannabis will develop a problem with cannabis use.
Risks of developing cannabis use disorder
The possibility that a person will develop cannabis use disorder depends on many factors. The risk factors for cannabis use disorder include:
- continued frequent and heavy cannabis consumption
- regular consumption of high-THC products before age 16 (or even before age 25, around the time the brain finishes developing)
- biological factors, such as a family history of substance misuse or mental illness
- social factors or your immediate environment, including the consumption of cannabis and attitudes toward it among your friends, family and community
9% of people who consume cannabis will develop problematic use patterns — that number rises to 17% for those who start consuming cannabis as teenagers. (For comparison, the CAMH 2014 Cannabis Policy Framework reported the probability of developing a dependence as about 68% for nicotine, 23% for alcohol and 21% for cocaine.)
25% to 50% of those who consume cannabis daily will develop cannabis use disorder.
Males are at a higher risk of developing cannabis use disorder, but females typically progress more quickly to cannabis use disorder than males. cannabis use disorder, but females typically progress more quickly to cannabis use disorder than males.
Understanding cannabis use
Cannabis use can be considered on a spectrum, ranging from abstinence to cannabis use disorder. While your reasons for consuming cannabis may change, you may move back and forth along the spectrum or never progress to problematic use. It’s important to know that cannabis use is not without risk, but there are ways to reduce that risk.
What is “regular” cannabis use?
There is no scientific consensus on the definition of “regular” cannabis use (also called chronic, frequent or long-term use). In general, the term refers to weekly or more frequent consumption that occurs regularly for a few months or years.
While research into cannabis is constantly evolving, we do know that regular cannabis use can have adverse effects on your health.
What is “heavy” cannabis use?
“Heavy use” describes daily (or more frequent) cannabis consumption. Compared with occasional use, heavy use, particularly of high-THC products, is associated with a greater risk of developing tolerance, dependence and cannabis use disorder.
Tolerance, dependence and withdrawal
Regular cannabis consumption can affect how your body responds to cannabis over time. For some people, this may lead to tolerance, dependence and withdrawal symptoms.
Starting with a low dose and increasing it gradually can help you limit the risk.
Tolerance and cannabis use
Regular cannabis use will lead to develop a tolerance — you become accustomed to a specific dose and feel you need to consume more to experience the same effects.
Starting with a low dose and increasing it gradually can help you reduce the risk of developing tolerance. If you've noticed that cannabis isn't affecting you the way it once did, reducing your THC consumption may help lower your tolerance. Taking a complete break from cannabis for several days or longer can be even more effective. This strategy is known as a tolerance break, or T-break.
Withdrawal syndrome in people who have cannabis use disorder
Research shows heavy cannabis consumption, particularly of high-THC products (consuming daily or almost daily) can cause psychological and/or physical dependence — you may feel anxious when you can’t consume cannabis or develop withdrawal symptoms after stopping.
Symptoms of cannabis withdrawal vary among individuals, but they typically include irritability, sweating, nausea, insomnia and body aches. The length and severity of withdrawal will vary too, depending on the dose and how long you’ve been consuming cannabis.
Can you overdose on cannabis?
It's possible to consume more cannabis than your body can comfortably handle. While this is different from the life-threatening overdoses associated with some other substances, overconsumption can still occur and may result in cannabis poisoning, leading to a range of unpleasant symptoms. If this happens, you might experience:
- severe anxiety
- paranoia
- vomiting
- potential for temporary drug-induced psychosis
These symptoms are temporary and often improve as the effects of cannabis wear off.
THC effects on brain
While consuming too much cannabis can lead to unpleasant symptoms and cannabis poisoning, it does not act on the brain in the same way as substances such as opioids, which can slow or stop breathing during an overdose. That is why there have been no documented cases of death solely attributable to cannabis overconsumption. In contrast, opioids and alcohol can affect the parts of the brain responsible for vital functions such as breathing. In cases of severe overconsumption, this can lead to respiratory failure and death.
However, cannabis poisoning can be serious, especially when it comes to children and pets, because of their small size and weight. Always keep your cannabis safely stored out of reach in a secure child-proof container to prevent unintentional consumption.
Cannabis use disorder treatment
If you’re experiencing particularly unpleasant or harmful effects from using cannabis, Health Canada suggests you stop consumption and seek immediate medical attention or call your local poison control centre. The same advice applies to accidental consumption by a child or pet.
When it comes to cannabis use disorder or addiction, there is no universal, one-size-fits-all treatment. Drug dependence treatment options include:
- cognitive behavioural therapy (CBT) and other psychological counselling therapies
- medications to treat withdrawal symptoms
- using alternative delivery methods
- helplines and in-person support
- help from your family doctor or a nurse practitioner
Free, confidential help for addiction, mental health and cannabis consumption is available in Ontario. If you are concerned about your or someone else’s cannabis consumption, Health Canada suggests discussing it with your physician or another trusted healthcare provider, or reaching out to a support group that deals with addiction (this does not replace professional screening for or treatment of cannabis use disorder).
You can also follow the Centre for Addiction and Mental Health Canada’s Lower-Risk Cannabis Use Guidelines.
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