Not everyone develops problems when using cannabis, but those who do can experience
side effects ranging from panic and anxiety when intoxicated, through to developing a dependency on cannabis after using the drug regularly over a period of time.
Although some people are more at risk of developing problems than others, these symptoms can and do arise at any stage of cannabis use.
There is much debate over whether cannabis itself causes mental health problems. For some people, there are very strong associations between the use of cannabis and either developing some mental health symptoms or making a condition they may already have worse.
Cannabis use has been linked to the following mental health conditions:
People already diagnosed with or experiencing symptoms related to any of these conditions should avoid using cannabis. If they do use the drug, they should talk to their doctor or healthcare worker about their cannabis use. This also applies to anyone who uses cannabis and has a family history of mental illness.
For more information, see the factsheet 'cannabis and mental health'
Young people
Generally speaking, if a person starts smoking cannabis at an early age (i.e., early adolescence) and uses cannabis frequently, they are more likely to experience negative consequences.
Young people using cannabis are at greater risk of:
The following factors may increase the risk of developing problems with cannabis use:
For more information please see the factsheet 'cannabis and young people'.
Factsheet published June 1, 2008. Updated October 1, 2011.