Cannabis & Schizophrenia
We've undertaken a survey that has revealed that more than 1 in 3 (35%) of 25-34 year olds agree or strongly agree with the statement “experimenting with cannabis is a normal part of growing up”
45 per cent failed to link smoking cannabis over a sustained period of time to schizophrenia.
The poll also showed that those aged 18-24 have less liberal views on cannabis than the 25-34 age bracket, with just 24% agreeing with the same statement.
Cannabis facts
Cannabis can be a confusing subject - some people seem to use it without getting mental health problems. So what are the facts?
- If you use it when young:
International studies have found that cannabis use doubles or triples the chances of developing psychosis if you smoke when you’re under 18. The more you use, the greater the risk – in two studies, those who had used cannabis more than 50 times had 6 times the usual risk of developing schizophrenia. Most recently, a 2011 study commissioned by the German government found that cannabis use doubles the rate of self-reported experience of psychotic symptoms in adolescents over a 10 year period. - If you use a lot of cannabis:
Smoking heavily at any age is also associated with mental health problems.
A 2008 study carried out by the Institute of Psychiatry (UK) found that people who had a psychotic episode were twice as likely to have used cannabis for longer, three times more likely to have used it every day and 18 times more likely to use skunk (a form of cannabis containing high levels of the active ingredient, 'THC'). - If you already have a psychotic illness:
If you have a psychotic illness, cannabis use severely reduces your chances of getting better. - Why doesn't it affect everyone?
Not everyone will be affected by cannabis use – like peanuts, cannabis is very dangerous for some people, but not such a problem for others. Rethink Mental Illness is not claiming that cannabis causes psychosis in everyone who uses it. One study has suggested that this is because of people having different genes, but this has not yet been confirmed. - How many people are affected?
Two studies have estimated that 13% of schizophrenia could be averted if all cannabis use were prevented. One of these says that 50% of the most serious cases would be avoided. - What does Rethink Mental Ilness want the Government to do?
We want a major public health campaign, like the campaign on smoking. The French Government spent over £3million Euros on a campaign about cannabis and mental health. And more research - no studies so far have been funded by the UK Government. - What about classification?
We think cannabis is a health issue; jailing people for cannabis use will not solve the problem. Money spent on policing cannabis should be spent on health education, services and research.
Smoking cannabis is playing a game of Russian roulette with your mental health.
Paul Jenkins, Rethink Mental Illness
Isn’t cannabis a medicine?
Cannabis is a very complex substance, with over 60 active ingredients. It’s a bit like crude oil – there are lots of different substances within it, all of which have different effects. One ingredient, THC Delta-9-tetrahydrocannabinol (THC), gets you 'high'. Another ingredient, Cannabidiol (CBD), relieves pain and prevents nausea
Cannabis grown for cannabis-based medicines is designed to have very low THC. So it is a chemically different substance from the cannabis sold on the street, which is designed to have very high THC and small amounts of the other ingredients.
One other ingredient in cannabis (cannabidiol) has been trialled as a treatment for psychosis. Rethink Mental Ilness supports this research and hopes it will produce a medicine that is effective for people with psychosis.
