New NHS clinic for treating cannabis psychosis overwhelmed by demand

NHS England has opened its first clinic dedicated to treating psychosis caused by smoking cannabis.

Based at the Maudsley Hospital in London, it is already overwhelmed by referrals for treatment.

Research published by the University of Bath in 2020 shows the potency of cannabis has increased over the past 50 years and the drug is becoming progressively worse in its effects.


Former user Ad Gridley suffered severe, long-term psychological effects, including hearing voices and paranoia, through his cannabis addiction.

Gridley attempted to take his life on six occasions and was admitted to an acute psychiatric ward multiple times before he finally saw dope as “the enemy” and the cause of his psychosis.

Along with other addicts, Gridley has been helped by the cannabis clinic. Oli, 25, is “rebuilding” his mind after requiring hospital treatment for numerous psychotic episodes.

Another patient, who had similarly been in and out of psychiatric units with psychosis, said: “There was a point when it was, like, oh, it’s only a joint, it’s not too bad — and 16 years later I’ve only just put it down.”

Clear link

Dr Marta Di Forti, a member of the team from King’s College London which oversees the clinic, told The Times there is a “clear” and “evidenced link” between cannabis and psychosis.

clear and evidenced link between cannabis and psychosis

She said: “Young adults with psychosis who continue to use high-potency cannabis report more severe psychotic symptoms, they are more likely to relapse and more likely to be readmitted to hospital — and for longer.”

Dr Di Forti added: “It has never happened to date that one of the people in the clinic has said, ‘Now I’ve stopped using cannabis, I still don’t think it had anything to do with my psychosis.’

“In the end, they realise the connection.”

Also see:

Psychosis and ‘scromiting’ on the rise among young US cannabis users

‘Cannabis killed my daughter’

Teenage cannabis use linked to premature births