“Regular cannabis smokers are 7 times more at risk from mental illness”

Fresh fears are being raised about links between cannabis and mental illness as a study by a top psychiatrist warns the risk of developing problems is seven times greater amongst regular heavy cannabis users.
Speaking at the Royal College of Psychiatrists’ annual conference in Edinburgh Professor Robin Murray of the Institute of Psychiatry said: “In the last 18 months a number of studies have confirmed that cannabis consumption acts to increase later risk of schizophrenia. This research must not be ignored.”The findings come as the Government prepares to downgrade cannabis from a Class B to Class C drug next year.Most people caught in possession of a small amount will have the drugs confiscated and receive a reprimand or warning, the Home Office has said.According to a Government fact sheet, cannabis “can cause psychotic reactions amongst individuals with mental health problems”, but it does not suggest use of the drug can prompt those problems.For his study, Professor Murray reviewed research in Sweden, Holland and New Zealand.

A recent Dutch study of 4,000 people in the general population showed that those taking large amounts of cannabis were almost seven times more likely to have psychotic symptoms three years later.
Another study, in 1987, of 50,000 Swedish Army conscripts, found that those who admitted at age 18 to having taken cannabis on more than 50 occasions, were six times more likely to develop schizophrenia in the following 15 years.
And the study in New Zealand found that those who used cannabis at age 15 were four and a half times at higher risk of developing psychosis by the age of 26.
Marjorie Wallace, chief executive of the mental health charity Sane, reiterated her opposition to plans to re-classify cannabis.She said: “These studies are showing links between cannabis and schizophrenia, and illnesses like it, which we have suspected anecdotally for many years. “In many instances cannabis is the trigger for the first schizophrenic breakdown. We would oppose re-classification.” But she said if ministers were “set on” downgrading cannabis to a Class C drug, the Government should invest in greater drugs education for schools.
Dr Connie Fozzard represents Cornwall for the British Medical Association and she says the current laws against cannabis are not working. “Clearly prohibition is not working and it never will work in any form when half the population doesn’t agree with the law. “What need is much more evidence as to what the benefits or disadvantages of these drugs are and we need much more research on these drugs.”