Psychosis may be associated with strong cannabis

Smoking potent ‘skunk-like’ cannabis increases your risk of serious mental illness, say researchers.

They estimate around one in 10 new cases of psychosis may be associated with strong cannabis, based on their study of European cities and towns.

In London and Amsterdam, where most of the cannabis that is sold is very strong, the risk could be much more, they say in The Lancet Psychiatry.

Daily use of any cannabis also makes psychosis more likely, they found.

Experts say people should be aware of the potential risks to health, even though the study is not definitive proof of harm.

Lead researcher and psychiatrist Dr Marta Di Forti said: “If you decide to use high potency cannabis bear in mind there is this potential risk.”

Dr Adrian James from the Royal College of Psychiatrists said: “This is a good quality study and the results need to be taken seriously.”