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Marijuana and mental health

3-minute read

Marijuana or cannabis is one of the most commonly used illicit drugs in Australia. It can make you feel chilled, but it also causes dependence, memory problems, paranoia and psychosis.

Marijuana is made from the dried leaves and flowers of a plant called Cannabis sativa. It’s also called dope, pot, grass, spliff, weed and joint. It’s usually smoked through a joint (like a cigarette) or through a bong or water pipe.

It’s illegal to use, possess, grow or sell cannabis in Australia. The penalties are different in each state.

Marijuana effects

Marijuana affects everyone differently. It can make you feel relaxed and happy, or quiet and reflective. The effects are felt soon after smoking it. But marijuana can also have harmful physical effects. Find out more about so called party drugs, including where to find help and support.

Mental health issues

Anyone who has an existing mental health issue or who has a close family member with depression, psychosis, bipolar disorder or anxiety should avoid marijuana, as they are at particularly high risk of mental health problems being caused by the drug.

Marijuana can trigger a psychotic disorder like schizophrenia in people who are already at risk of developing the disorder. In these people, marijuana may mean they develop the problem earlier.

People who use marijuana have been shown to have higher levels of depression and depressive symptoms than those who do not use it. It can also lead to temporary symptoms of anxiety such as panic.

Learn more about how marijuana affects mental health.

Marijuana can cause:

People who use marijuana over long periods can:

  • become dependent
  • lose their sex drive
  • have problems with their memory
  • have learning difficulties
  • have mood swings
  • become psychotic, if they have schizophrenia or are at risk of psychosis
  • think about suicide

People who use marijuana are more likely to have social and financial problems, do poorly at school, and have family and relationship issues.

Marijuana is particularly risky for people who have mental illness in the family.

Not sure what to do next?

If you or someone you know are finding it difficult to manage mental health issues as a result of drug use, try healthdirect’s Symptom Checker and get advice on when to seek professional help.

The Symptom Checker guides you to the next appropriate healthcare steps, whether it’s self care, talking to a health professional, going to a hospital or calling triple zero (000).

Kicking the habit

People who use marijuana repeatedly for long periods can become dependent on it. If they stop using, they might feel anxious, irritable and angry, not feel like eating and have trouble sleeping.

Find help on the Alcohol and Drug Foundation website.

You can also call Lifeline on 13 11 14, DrugInfo on 1300 85 85 84 or the National Alcohol and Other Drug Hotline on 1800 250 015 if you need to talk to someone about drugs.

Learn more here about the development and quality assurance of healthdirect content.

Last reviewed: July 2019


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