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Cannabis

Cannabis is a psychoactive drug that is used for recreational and medical purposes.

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Official Name

​Cannabis

Street Name

Cannabis (marijuana, weed, pot, bud, green, herb or flower), hash, extracts (honey oil, phoenix tears, shatter), edibles

What is it?

Cannabis is a product of the cannabis sativa plant that is used for its psychoactive and therapeutic effects. It comes in many forms, including as dried flowers and leaves; hash; extracts, such as oil (e.g., honey oil, phoenix tears) and shatter; and edibles (e.g., candies, butter or baked goods).

Cannabis contains hundreds of chemical substances. More than 100 chemicals, called cannabinoids, have been identified as specific to the cannabis plant. THC (delta-9-tetrahydrocannabinol) is the main psychoactive cannabinoid and is most responsible for the “high” associated with cannabis use. Another cannabinoid is cannabidiol (CBD). CBD has little or no psychoactive effects, so you do not feel high. CBD counteracts some of the negative effects of THC.

Where does it come from?

The cannabis sativa plant is native to tropical and temperate climates but is cultivated around the world.

What does it look like?

Cannabis is the dried flower buds and leaves of the cannabis plant. Its colour ranges from grayish-green to greenish-brown and may contain seeds and stems. Hash is the dried, compressed resin of cannabis flower buds. It ranges in colour from brown to black, and it is sold in chunks. Oil is made by boiling cannabis flower buds or resin in an organic solvent, which produces a sticky reddish-brown or green substance. The THC content of each variety of cannabis varies, although hash is generally more potent than the plant, and oil is usually the most potent form of cannabis.

Cannabis can be used in many different ways. For instance, it may be rolled into a cigarette (called a joint), mixed with and rolled into a joint (called a spliff), or packed into a pipe or bong and then smoked. Cannabis can also be vaped. The extracts (such as oil or shatter) are often dabbed with an oil rig pipe, called a dab rig. Cannabis may also be used as an ingredient in food.

Who uses it?

According to the Canadian Tobacco, Alcohol and Drugs Survey , 3.6 million (12 per cent) of Canadians used cannabis in 2015. Of that population, 24 per cent said they used cannabis for medical reasons.

How does it make you feel?

How cannabis affects you depends on:

  • how much you use
  • how often and how long you’ve used it
  • whether you smoke, vape or eat it
  • your mood, your expectations and the environment you’re in
  • your age
  • whether you have certain pre-existing medical or psychiatric conditions
  • whether you’ve taken any alcohol or other drugs (illegal, prescription, over-the-counter or herbal).

People can have very different experiences with cannabis. Some may feel relaxed, lively, talkative, giggly and even euphoric, while others feel tense, anxious, fearful and confused. The kind of experience you may have can vary from one drug-taking episode to another, usually because of the amount taken, the method used and the frequency of regular cannabis use.

The physical effects of cannabis may include:

  • red eyes
  • dry mouth and throat
  • irritated respiratory system (from smoking)
  • increases in appetite and heart rate
  • decreases in blood pressure, balance and stability
  • drowsiness or restlessness, depending on the amount taken and individual response to the drug.

However, the therapeutic uses of cannabis are associated with its ability to regulate (and manage):

  • nausea (e.g., for chemotherapy patients)
  • appetite (e.g., for people with cancer or HIV/AIDS)
  • pain (e.g., for people with multiple sclerosis, cancer-related pain or chronic pain that is not cancer-related)
  • depressed mood and insomnia (e.g., for people who have chronic diseases).

How long does the feeling last?

When cannabis is smoked or vaped, the effect is almost immediate and may last several hours, depending on how much is taken. When it is swallowed, the effect is felt in about an hour and lasts longer than when it is smoked.

Although the high lasts only a few hours after smoking, THC is stored in fat cells and expelled from the body over a period of days or weeks. This is why drug tests for cannabis use can give a positive result long after the effects have worn off.

Is it addictive?

People who use cannabis regularly can develop psychological and/or mild physical dependence. People with psychological dependence may be preoccupied with using cannabis, and if they can’t get it, they feel anxious.

After regularly using cannabis for a long period of time, people can develop physical dependence. If they stop using, they may experience mild withdrawal. Symptoms can include irritability, anxiety, upset stomach, loss of appetite, sweating and disturbed sleep. These symptoms generally last for about a week, but sleep problems may continue longer.

Is it dangerous?

Those who use cannabis should be aware of the health risks and take measures to avoid them. The following health risks are possible for anyone who uses cannabis heavily or regularly:

  • problems with thinking, memory or physical co-ordination
  • impairment, which can lead to serious injuries, including those from car accidents
  • hallucinations, such as seeing, hearing, tasting, smelling or feeling things that do not really exist
  • mental health problems, specifically if you or an immediate family member has had a mental health issue, like psychosis or an addiction to alcohol or other drugs
  • cannabis dependence
  • breathing or lung problems from smoking
  • cancer from smoking
  • problems during or after pregnancy, especially if cannabis is smoked

For more information about these risks and ways to avoid them, Canada's Lower-Risk Cannabis Use Guidelines may be helpful.

 

Sources:
Do You Know… Cannabis © 2010 Centre for Addiction and Mental Health
Lower-Risk Cannabis Use Guidelines © 2017 Centre for Addiction and Mental Health, Canadian Research Initiative in Substance Misuse
Consumer Information—Cannabis © 2016 Health Canada
Information for Health Care Professionals: Cannabis (marijuana, marijuana) and the cannabinoids © 2013 Health Canada
Tobacco, Alcohol and Other Drugs Survey © 2017 Government of Canada

Where can I find help, treatment and support?

  • Treatment at CAMH: Access CAMH
  • Help for families from CAMH 
  • ConnexOntario
  • Kids Help Phone at 1 800 668-6868

Where can I find more information?

  • Canada’s Lower-Risk Cannabis Use Guidelines (PDF)
  • A Framework for the Legalization and Regulation of Cannabis in Canada
  • Vaping: What you and your friends should know
  • Vaping: What elementary school educators need to know
  • Vaping: What secondary school educators need to know
  • CAMH Continuing Education: Addressing Cannabis Use in Primary Use

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