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Home » Charity warns over ‘safe’ legalisation of cannabis

Charity warns over ‘safe’ legalisation of cannabis

Charity warns over ‘safe’ legalisation of cannabis

9th Feb 2020

Psychosis link to high potency drug must be investigated, warn mental health chiefs

Rethink Mental Illness charity warns over damaging effects of cannabis on the mind. Photograph: David Bebber/REUTERS


One in 20 adults would take cannabis on a regular basis if it were legalised, similar to the number of people who currently use it, according to a poll for a leading mental health charity.


A particular concern is the use of high potency cannabis, or “skunk”, which increases the risk of developing psychosis. Psychosis can be a symptom of mental illness, including schizophrenia and bipolar disorder.

Sir Robin Murray, professor of psychiatric research and chair of the Rethink Mental Illness Clinical Advisory Group, said high potency cannabis was responsible for a third of all new patients in London being diagnosed with psychosis. “This is a clear indicator that our current system is not working,” Murray said.


Many pro-legalisation groups argue it would see the potency levels capped, reducing harmful effects, but Murray is dubious. “In the US, states that have legalised cannabis for recreational purposes have seen an increase in the use and potency of cannabis, and even more cannabis-related problems.