Cannabis is the most widely used illegal drug in Britain. Made from parts of the cannabis plant, it’s a naturally occurring drug. It is a mild sedative (often causing a chilled out feeling or actual sleepiness) and it’s also a mild hallucinogen (meaning you may experience a state where you see objects and reality in a distorted way and may even hallucinate). The main active compound in cannabis is tetrahydrocannabinol (THC).
In 2004 the Department of Health released figures that showed drug centres were reporting growing numbers coming to them with problems related to Cannabis. Nine per cent of all those attending clinics cited cannabis as the main reason they were attending, rather than any of the other drugs they were using, twice as many as a decade ago. A separate study by the World Health Organisation showing that one in five 15-year-olds in Britain smokes cannabis, more than twice the world average.
There is also increasing clinical evidence linking cannabis use to mental illness, particularly schizophrenia, psychosis, anxiety and depression. US research shows that 80 per cent of new cases of psychosis in some hospitals have been triggered by cannabis use. Someone who starts using cannabis aged 15 is at more than four times the risk of developing schizophrenia over the next 11 years than someone starting smoking the drug at 18. And 18-year-olds who have used cannabis at least 50 times have a seven-fold increased risk of developing psychosis in the next 15 years.