CANNABIS 'LINK TO SCHIZOPHRENIA RISE'

Softer Drugs Law Blamed For Risk of Mental Illness As Users Aim to Get
Heavily 'Stoned'

Stronger cannabis - and users getting stoned to a 'far more debilitating
degree' - could lead to a rise in cases of schizophrenia and present the
NHS with a much larger bill, a leading drugs expert will warn tomorrow.

Professor John Henry believes that the Government, in its decision to relax
the laws on cannabis, has overlooked the burden that greater use puts on
health services and on families - as well as the way young people are
seeking to heighten the effects of the drug.

Henry, a toxicologist and professor of accident and emergency medicine at
Imperial College London, will talk about the medical risks associated with
the drug at a conference tomorrow. He fears that several hundred more young
people could end up in hospital suffering from schizophrenia, and might
need anti-psychotic drugs to deal with their condition.

A year ago the Government announced plans to reduce the classification of
cannabis from category B to C, after a recommendation from the Police
Federation that it was far less harmful than other drugs. The
reclassification takes place this summer, and anyone caught smoking a joint
will be much less likely to be arrested or prosecuted for possession.

The policy change follows a controversial scheme in Lambeth, south London,
in which the Metropolitan Police decided to focus on hard drug users rather
than cannabis smokers. The Met said it achieved great results against hard
drug dealers, but some health workers were worried that children in the
area felt it was now legal - and safe - to smoke cannabis.

There is mounting concern among psychiatrists about the future impact of
the softening of the law. Three million people are thought to smoke
cannabis regularly, a quarter of them young adults under the age of 29. It
has been shown that more people are growing cannabis for their own consumption.

Some doctors have argued that cannabis can be highly beneficial for
patients suffering chronic pain, or those with multiple sclerosis.

However, Henry will warn at the Royal Society of Medicine's conference that
there has been a recent, dangerous shift in the way people use cannabis and
alcohol.

Recreational use has given way to a cultural acceptance of getting stoned
regularly to a 'far more debilitating degree', according to Henry. 'Modern
cannabis is nearly 10 times the strength the "flower power" generation was
used to, and in Amsterdam it is at least twice as strong as in the UK,' he
said. 'We know that for those who take the drug there is a fourfold
increase in schizophrenia and a fourfold increase in the chances of
suffering major depressive illness. Given that we know schizophrenia
accounts for some 3 per cent of the total NHS bill, the costs could go up
by another 1 per cent. That should be urgently considered by the Government.'

Henry believes there are emerging mental health problems associated with
THC, or tetrahydrocannabinol, the main active ingredient of cannabis, which
in greater concentrations makes more potent forms of the drug, such as 'skunk'.

To investigate its effects on the brain, a study is about to begin at the
Maudsley Hospital in south London. Volunteers will be offered free
cannabis, so that researchers can carry out brain scans and conduct memory
tests to see how mental activity is affected.

Professor Robin Murray, who is leading the study, said his view of the drug
had changed in recent years. He used to be sceptical when cannabis was
blamed. 'Relatives would say "It seems to be the cannabis that makes my son
or daughter or brother psychotic" and I would say, "Oh, they're being
hysterical, they're just trying to look for something to blame". We've come
to realise that it does have a significant effect, but it has taken us a
long time to wake up to this.'

Others, however, point to the fact that rates of schizophrenia have not
risen dramatically in the past 50 years to correspond with increasing use
of the drug. There is also a question over whether those who are likely to
develop schizophrenia are already predisposed to take cannabis.

Recent guidance on the provision of drugs for schizophrenia by the National
Institute for Clinical Excellence (Nice) estimated that treatment of
schizophrenia in England and Wales was responsible for around 3 per cent of
the entire NHS budget - some ?1 billion a year.

Cliff Prior, chief executive of Rethink, a charity helping those with
mental illness, said: 'The public needs to understand that this danger is
real. There is growing evidence that cannabis may trigger schizophrenia in
vulnerable people.'