May 1, 2007

Author: Fiona MacRae

JUST half a 'joint' of cannabis  can  trigger symptoms similar to schizophrenia, psychiatrists warned yesterday.  A  study  showed small amounts of the drug can lead to paranoia, hallucinations, delusions and other mental illnesses.  Although the symptoms did not last long, the research will fuel growing concerns about the damage  cannabis does to the body and society.  When  healthy men and women  were  given  small amounts of THC – the chemical which gives cannatais users their 'high'  – half developed the symptom's.  When the  strength of the drug was increased to the amount found in two joints, 60 per cent suffered the  side effects.  Schizophrenics appeared to be even mete vulnerable to the drug, despite  their illness being controlled with  medicine.  More than 28,000 people are hooked on cannabis in Ireland.  There were more than 6,000 court  prosecutions   for cannabis use in 2005. A total of 5,000 16-year-olds admitted to using the drug at least three times per month.  The cannabis market is worth 375million, more than the   combined share for cocaine, heroin, ecstasy and speed.

  The latest study comes amid warnings that the emergence of a superstrength cannabis known as skunk on the streets could create a mental health time bomb.  Researcher  Dr  Deepak D'Souza, of Yale University School of Medicine in the U.S., said:  'We had a subject who refused to answer any  of the questions   we  asked her because she was convinced that my staff could read her mind, so she didn't need to answer the questions. 'We had another subject who refused to continue with any of the tests because she thought we were trying to make her look stupid.' His research, which will be presented at a London conference on cannatais and mentalhealth this week, comes as another study shows far the first time how cannabis may trigger paranoia. Using sophisticated brain scans, researchers from the Institute of Psychiatry in London showed the drug stifles activity in the part of the brain responsible for inhibition.

Scans of the brains of healthy young men  revealed the greater the damping of emotion, the more paranoid the volunteers  felt.  Professor Philip McGuire, who carried out the research, said: 'Let's say you had a nagging thought about whether your boss was planning to sack you. 'These worrying thoughts are normally controlled and suppressed by this region. 'But if you unleash this region and stop it working,these thoughts might become more prominent.' Speaking ahead of the twoday conference, which starts today, his colleague Professor Robin Murray warned that youngsters may be especially vulnerable  to the  effect.
Research he completed in 2005 showed a clear link between cannabis use in the teenage  '28,000 hooked on cannabis' years and mental illness in later life. Those who smoked the drug regularly at.18 were 1.6 times, more likely to suffer serious psychiatric problems,including schizophrenia, by their mid-twenties. For those who were regular users at  the'age of 15, the stakes were even higher. Professor Murray's  research showed they faced a risk of developing mental illness that was 4.5 times greater than normal. The psychiatrist said it was likely that cannabis use in adolescence also had long lasting effects on memory.


Publication: Irish Daily Mail, Tuesday 1st May 2007, Page 21