The use of cannabis by young people is currently clouded in a
confusion that has nothing to do with the effects of the drug
itself. Muddled messages over its legal status and effect on health
have created uncertainty over exactly what risks people are taking
when they indulge in the nation’s favourite illicit substance.
Cannabis was reclassified on 29 January from a class B to class C
controlled substance. This puts it in the same legal category as
Valium and drastically reduces the penalties for possession (see
box). The move came after the Advisory Council on the Misuse of
Drugs concluded that “in terms of its inherent toxicity or
harmfulness” cannabis could no longer compare with other class-B
drugs such as the amphetamines.
However, on the day the reclassification was announced the
government also launched a £1m media campaign stressing that
cannabis remains illegal and that children and young people cannot
expect the same leniency as adults from the police.
This was followed a few weeks later by prime minister Tony Blair
telling the News of the World that head teachers would
soon be given powers to randomly drug test their pupils and exclude
those who proved positive or report them to the police. Under a
hail of protest the government later back-tracked, acknowledging
that such tests could only be carried out with pupils’ and parents’
Meanwhile, the British Medical Association, Royal College of
Psychiatrists and mental health charities have been at pains to
point out that the reclassification of cannabis should not be
interpreted as giving the drug a clean bill of health.
“Chronic cannabis smoking increases the risk of heart disease, lung
cancer, bronchitis and emphysema,” says Dr Peter Maguire, deputy
chairman of the BMA’s board of science.
In particular there has been growing concern at evidence linking
early cannabis use with the onset of psychotic illnesses such as
According to a study by the Institute of Psychiatry, people who use
cannabis before they are 15 are four times as likely as others to
have a diagnosis of schizophrenia or a related condition at age
The study also showed that young people who use cannabis before the
age of 15 are more likely to develop schizophrenia than people who
start using it between 15 and 18. “The earlier people start using
cannabis the greater their risk for developing psychosis,” says Dr
Louise Arseneault of the Institute of Psychiatry and principal
author of the paper.
The review was unable to establish whether cannabis was a direct
cause of the psychosis or whether it simply acted as a trigger in
already vulnerable young people. Not all adults with schizophrenia
have used cannabis in adolescence and most cannabis users do not
develop psychosis in adulthood, the study pointed out.
Nevertheless the authors estimate that if cannabis use could be
eliminated within the population it would reduce the incidence of
schizophrenia by about 8 per cent.
“Cannabis use among psychologically vulnerable young people should
be strongly discouraged by parents, teachers and health
practitioner,” they conclude.
At current levels of popularity, however, the idea of eliminating
cannabis use is ambitious. The most recent figures from the
Department of Health estimate that nearly one in three 15 year olds
have used cannabis in the past year. Clearly, for these young
people, cannabis’s class B status has failed to act as an effective
Paul Corrie, head of policy and campaigns at mental health charity
Rethink, acknowledges that education rather than criminalisation is
probably the best way to deter young people from using cannabis.
However, he feels that much of the information currently being
released from the government is weighted too heavily towards the
legal status of cannabis rather than its risks for mental health.
“We don’t have a view on reclassification itself. To be honest
cannabis is so widely available that anybody who would be using it
probably is already. However, we do feel that the government has
wasted an opportunity to really drive home the message on the risks
of severe mental illness. There’s been a lot of publicity from the
government around the fact that cannabis is still illegal, but not
very much on the risks to mental health.”
Certainly, the government appears to be concerned that the
reclassification of cannabis should not be misinterpreted as a step
towards legalisation. Home Office drugs minister Caroline Flint has
stressed the measures the government is taking to get the message
across that cannabis remains illegal and that under-18s will still
be arrested for possession.
“Using the radio ads alone we expect to reach 81 per cent of 15 to
17 year olds and 41 per cent of adults,” she says. “This is just
the beginning of an extensive campaign which will warn the public
about the legal, health and social effects of cannabis use.”
According to Andrew Bennett, director of the drugs information
charity HIT, concern over cannabis’s confused legal status is well
“There’s been confusion about the legal status of cannabis for
about 18 months now, ever since they first started talking about
reclassifying it,” he says. “Some young people seem to think it’s
legal now or at least that they won’t get busted for it.”
In contrast, Bennett believes that the health risks of cannabis are
well known by many of the young people who use it.
“HIT has done some research on this among cannabis users aged 15 to
50 and the results show that even among the youngest users, there
is a fair proportion who are aware of the health risks,” he says.
“They tend to be most aware of the risk of respiratory illness, the
tobacco-related problems and cancer. They are less aware of the
risk of psychosis.”
Bennett welcomes the reclassification of cannabis – “although I
would go further” – and rejects the suggestion that the reduced
legal penalties for possession are likely to result in an increased
number of young people using the drug.
“For a large proportion of young people I don’t think it will make
much difference at all. If you look at other countries that have
gone down this route, then there’s no evidence that greater
tolerance increases the use of cannabis. The Netherlands, for
instance, has got 30 years of tolerance behind it and their young
people are less likely to use cannabis than ours.”
“All [prosecuting cannabis users] does is criminalise a huge swathe
of young people and the effect of that can be far more devastating