Pubdate: Sun, 22 Feb 2015 Source: Mail on Sunday, The (UK) Copyright: 2015 Associated Newspapers Ltd. Contact: http://www.mailonsunday.co.uk/ Details: http://www.mapinc.org/media/255 Author: Stephen Adams, Health Correspondent CLEVER TEENAGERS MOST AT RISK OF 'SKUNK' PSYCHOSIS BRITAIN'S brightest teenagers are among those most at risk of mental illness caused by smoking a potent form of cannabis, a leading expert has warned. Professor Sir Robin Murray said it tended to be 'clever and sociable' youngsters who were damaged by using the super-strong strain of the drug, known as skunk. Sir Robin, the foremost authority in Britain on the effects of smoking cannabis, led a landmark study with colleagues at the Institute of Psychiatry which found that regularly smoking skunk triples the risk of psychosis, as revealed last week by The Mail on Sunday. Now he has given further alarming warnings after his study was published in full in The Lancet Psychiatry. Speaking yesterday, he said that: Skunk now dominates Britain's cannabis market - and is so widely used that it has become a gateway drug to tobacco. It is having a devastating impact on mental health - leaving some people with permanent schizophrenia. Cannabis has been 'effectively decriminalised' in South London. Teens are now legally purchasing ultra-strong synthetic cannabis online - without knowing it is even more likely than skunk to trigger psychosis and acute paranoia. Sir Robin said: 'Twenty-five years ago, if parents, brothers or sisters of a patient with schizophrenia asked me: "Could it have had anything at all to do with the cannabis he smoked?", I'd have said: "There's no evidence that's the case don't worry about it." All the medical journals said cannabis was a safe drug. But now we know there are these risks.' He said: 'A lot of people who develop schizophrenia have had problems since they were children. Maybe they had more personality or cognitive difficulties than their brothers or sisters. But the ones who develop psychosis associated with cannabis, they tend to be people who were doing very well. 'Their parents always say: "No I never worried about them at all - they had lots of friends, were good at school, good at sport." 'In some ways their problem was that they were so sociable: they were street-smart and could get cannabis when they were 13. 'So it's a different group of people who get psychotic as a result of cannabis: they were cleverer and more sociable before they got ill.' People who had suffered a single psychotic episode - such as hallucinations or delusions tended to get better if they gave up smoking skunk, with no long-term effects. But, he said 'sadly a proportion won't recover', adding: 'A third of people with cannabis-induced schizophrenia don't stop . . . people who persist in smoking cannabis have the worst outcomes. Someone who's smoked regularly for five years, they don't recover. It just looks like regular schizophrenia.' Last week's study concluded that 24 per cent of 'first episode psychosis' cases in South London were caused by smoking skunk. South London is a known cannabis hot-spot. But Sir Robin believed skunk was now widely available 'across the country', with research showing three people now smoked skunk for every individual smoking 'old-fashioned', weaker hash. Cannabis use was as big a health problem in the young as smoking cigarettes, he said. 'It used to be that people started smoking cigarettes and then moved on to cannabis. Now, for increasing numbers, it's the other way around.' The drug had been 'effectively decriminalised, at least in South London where I work', he said, as the police 'won't arrest somebody simply because they have cannabis for their own use'. Increasing numbers of teenagers, wanting to stay on the right side of the law, are buying 'legal highs' off the internet. These chemicals, marketed as 'spice' or 'incense', are designed to mimic the effects of cannabis. But Sir Robin said they could be much more powerful than skunk. Users of 'synthetic cannabinoids' are far more likely to end up in A&E than those who smoke pot, according to Dr Adam Winstock of the Institute of Psychiatry. 'Little 14-year-olds who'd like to experiment, but don't want to do anything illegal, buy things off the internet that are legal, but also more potent,' said Sir Robin. 'It's sad that some kid may end up taking something worse [than cannabis], by getting it in a brownpaper envelope through the post.' - --- MAP posted-by: Jay Bergstrom