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Marijuana and mental health

3-minute read

Marijuana 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. Learn more about the impact of illegal drug use.

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

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.

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).

Last reviewed: September 2017

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