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How Marijuana Effects Health

Marijuana, like other drugs, can be harmful to your health. The risks are increased when use begins in the teen years and when marijuana is used on a daily or near-daily basis. People with a history of drug and/or mental health problems are also at an increased risk for experiencing harms related to marijuana use.

What are the short-term risks of using marijuana?              

Marijuana has different effects on different people which vary depending on many factors including the type and amount of product used. Some people who use marijuana may feel relaxed and happy. Others may become quiet and withdrawn or experience severe anxiety, panic attacks, fearfulness and paranoia.

Some of the immediate physical effects of marijuana are red eyes, increased heart rate, drop in blood pressure, and light-headedness. When high on marijuana people may also experience altered senses (for example, seeing brighter colors), altered sense of time, reduced balance and coordination, difficulty with thinking and problem-solving and difficulty remembering things.

These effects usually disappear within a few hours but can last longer, especially if the drug is consumed in edible form. Driving or operating machinery after using marijuana is not safe, especially if combined with other drugs, including alcohol.

What are the long-term risks of using marijuana?

The Developing Brain and Mental Health

Regular use of marijuana during the teen years can harm the developing brain and is linked to the development of schizophrenia in certain people and with other mental health issues such as depression and anxiety. Regular use of marijuana has been shown to negatively impact a teen’s perception, memory, judgment, and reasoning. These changes can reduce a young person’s motivation and school performance, as well as negatively affecting decision making and increasing risk taking behaviour.

Your Lungs

Regular use of marijuana can affect your lungs and lead to conditions such as cough, wheeze, worsening of asthma, sore throat, chest tightness, and shortness of breath. Marijuana smoke contains many of the same chemicals as tobacco smoke, several of which are known to cause cancer.

Marijuana and Pregnancy

A growing body of research shows that marijuana use during pregnancy may negatively impact a child’s cognitive and behavioral development. This may lead to lower academic achievement and behavioural difficulties, including attention deficits, increased hyperactivity and impulsivity. At this time, there is very limited research available on the effects of a child’s exposure to marijuana through breastmilk. Given that there is still limited research in this area it is safest for women who are pregnant or breastfeeding to avoid marijuana use altogether. If you have questions about marijuana use during pregnancy and breastfeeding, speak with your health care provider.

Click here for more information on the Risks of Cannabis on Fertility, Pregnancy, Breastfeeding and Parenting.

Is Marijuana Addictive?

While many people think that marijuana is relatively non-addictive, the potential for someone becoming addicted to the drug is in the same range as alcohol.

Dependence on marijuana develops after repeated or regular use. Individuals who develop an addiction to marijuana typically:

  • Want to use all the time-even when they didn't plan to
  • Spend a lot of time thinking about and using marijuana
  • Need a greater amount of marijuana to get the same effects
  • Continue to use marijuana even though it is causing physical or social problems

Need help?

If you or somebody you care about experiences difficulty controlling their use seek professional help.  For resources in your community contact:  Connex Drug and Alcohol Help Line.


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