The cannabis market is almost completely dominated by the dangerous super-strength ‘skunk’ variety blamed for triggering psychotic disorders, a major study has found.
The potent strain has all but forced out the lower-strength form of the drug, and made up 94 per cent of all cannabis seized in 2016.
In 2005, just 51 per cent of cannabis seized was skunk.
The cannabis market is almost completely dominated by the dangerous super-strength ‘skunk’ variety blamed for triggering psychotic disorders
The study – led by King’s College London – analysed nearly 1,000 samples of cannabis seized by police in drug raids in London, Kent, Derbyshire, Merseyside and Sussex.
Psychiatrists have warned that smokers of the ‘high-potency’ cannabis have a greatest risk of spiralling into mental illness, with young people especially vulnerable. A series of cases have highlighted the link between the potent drug and mental health problems.
Dr Marta Di Forti, a clinician scientist at King’s College London, said: ‘In previous research we have shown that regular users of high-potency cannabis carry the highest risk for psychotic disorders, compared to those who have never used cannabis. The increase of high-potency cannabis on the streets poses a significant hazard to users’ mental health, and reduces their ability to choose more benign types.’
The study, published in the journal Drug Testing and Analysis, found that the rise in skunk’s popularity had been mirrored by a fall in availability of weaker cannabis resin, which has a THC content of 6 per cent, up from 4 per cent in 2008, but a lot lower than the 14 per cent found in skunk. THC is the compound which gives users a ‘high’.
Resin’s share of the illicit drug market fell from 43 per cent in 2005, to 6 per cent in 2016.
In London it is even lower, with 99 per cent of cannabis seizures comprising skunk.
One of the reasons skunk is so harmful is that it contains very low levels of a compound called CBD, which prevents psychosis. CBD content is 0.29 per cent, compared to 6 per cent in resin. Dr Di Forti, a practising psychiatrist, said: ‘If the availability of skunk goes up, there is a risk we will see a greater number of people developing psychosis.’
She added that based on previous research, if young people smoke skunk daily they push up their risk of developing psychosis from one in 100 – the risk for non-drug takers – to one in 20.
Dr Di Forti said: ‘We know that saying ‘Don’t do this, don’t do that’ to teenagers can have the opposite effect, but my advice is that important changes are happening to your brain and substances that can have an effect on your brain can alter it.
‘No drugs should be used when the brain is developing.’
Colleague Dr Tom Freeman said: ‘This valuable study… clearly shows that the illicit UK cannabis market is more dominated by harmful forms of cannabis than ever before. This data may help to explain why an increasing number of young people are now seeking professional treatment for cannabis problems.’
Professor Valerie Curran, professor of psychopharmacology, UCL, said: ‘Evidence from our own previous research at UCL suggests that high-potency varieties are more likely to lead to addiction, so if the market is dominated by these varieties, then this inevitably puts more people at risk of addiction.’
Schizophrenic high on drug knifed two nurses
A paranoid schizophrenic stabbed two health professionals before setting fire to a secure unit after smoking up to £60 of skunk a day, a court heard.
Myha Grant’s use of the drug, as well as the former legal high Spice, was said to have ‘destabilised’ his mental state.
The 31-year-old was a patient at the Bracton Centre in Dartford, Kent, in July last year when he went on a knife rampage, shouting ‘Allahu Akhbar’ as he repeatedly slashed nurse Julius Falomo.
Myha Grant (pictured) stabbed two health professionals before setting fire to a secure unit after smoking up to £60 of skunk a day
Mr Falomo suffered 17 life-threatening wounds while his colleague, health care assistant Francis Barrett, was stabbed at least six times. Grant was at the medium security psychiatric unit following an unprovoked, random attack in Brixton, south-west London, when he struck a man in the head with a champagne bottle.
Maidstone Crown Court in Kent heard earlier this month that Grant’s drug abuse started at 13, and by 16, he was smoking up to £60 of skunk cannabis a day. The shop worker has since been diagnosed with several mental conditions.
After stabbing the two health workers, Grant set fire to a pile of his clothes.
Prosecutor Simon Taylor said Grant was crying out ‘Allahu Akhbar’ and ‘Jah Rastafa’ as he repeatedly stabbed Mr Falomo.
Grant, who was initially charged with attempted murder, admitted two offences of wounding with intent and one of arson. He has been detained in Broadmoor hospital for 16 years.
Judge Jeremy Carey said: ‘Your history of smoking cannabis from a young age, and in substantial quantities and regularly, and your use of Spice, suggests in a psychiatrist’s opinion destabilisation of your mental state, leading to an increase in your psychotic symptoms and level of paranoia.’