As scans show drug’s impact on brain, a top doctor warns of a psychosis, paranoid delusions and a superskunk schizophrenia timebomb

Britain could set off a schizophrenia timebomb if it ignores the dangers of super-strength ‘skunk’ cannabis, one of the UK’s most eminent psychiatrists warns today.

Strong evidence now shows that smoking potent forms of the Class B drug increases the chance of psychosis, paranoid delusions and schizophrenia.

But too many people – from teenagers to top officials – have little idea of the terrible toll it can take on the mind, says Professor Sir Robin Murray.

Labour, the Liberal Democrats and the Scottish National Party all back legalisation of cannabis in some form. But Prof Murray said the dangers were not being recognised – and legalising skunk would amount to ‘a major pharmaceutical experiment’ with the brains of young people.

Prof Murray, from the Institute of Psychiatry at King’s College London, said: ‘I don’t think any serious researcher or psychiatrist would now dispute that cannabis consumption is a component cause of psychosis.’

He warned that:

  • MRI scans show long-term use of skunk can shrink a vital part of the brain;

  • The substance – now dominant on Britain’s streets – is four times stronger on average than cannabis smoked in the past;

  • A clear majority of studies show those who regularly smoke cannabis are at ‘significant increased risk’ of developing psychosis or schizophrenia-like illness;

  • Heavy users of skunk are up to four times more likely than non-users to develop psychotic symptoms.

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Even with its pernicious effect on the brain, I still believe marijuana is less dangerous than alcohol. I’ve seen marijuana do enormous damage, but every year we lose tens of thousands of lives to drunk driving accidents on our highways.

The article got some basic information wrong about cannabis. It compares skunk to marihuana when skunk is a strain of marihuana. And it’s thc content is most typically less than hashish, as hash is a concentrated form of cannabis. Whereas the article was falsey saying skunk was more potent. And another poster brought up an interesting article that found rates of schizophrenia remained the same while cannabis use amongst various groups had increased

In my own view it is an issue of genetic vulnerability and early stressors. I know some serious substance abusers who use alot of cannabis and I’m the only one I know with a psychotic disorder. I used cannabis yes but my substance use was absolutely nothing compared to these friends I am mentioning. I would expect I have some genetic predisposition for psychotic bipolar all these others I mention don’t have. They likely though have more genetic vulnerability for substance abuse since many these same individuals I know are also alcoholics. I recall hearing a plausible explanation for the connection of cannabis and psychotic disorders could be that the groups often come from troubled circumstances and may be trying to self medicate


Thank you for sharing this. Not many people know this.

I smoked skunk weed. And I got really messed up.

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All I see is the need to create regulations on THC content. Put it at a safe level where it can be enjoyed over time.

But I bet they are going to use this to keep it outlawed.