Marijuana study: Does smoking skunk really cause psychosis?

There’s a new study on the relationship between cannabis and psychosis, the apparent conclusion of which is that super-strong skunk is causing around one in four of new psychosis cases in the UK.
Data obtained from 780 south Londoners, more than half of whom were patients with first-episode psychosis, suggests that people who smoke particularly potent marijuana are more likely to experience a psychotic episode than those who don’t — or those who smoke hash instead.

It is, however, problematic to extrapolate on this small-sized sample, chosen specifically because of the area’s notorious cannabis predilection; the researchers themselves state their conclusions carefully.
As ever with these sorts of studies, there remain questions over the reliability of self-reporting and whether these skunk smokers were already psychologically vulnerable.

Though it might be a step to far to use as evidence that weed is to blame for a quarter of ‘all new serious mental disorders’ – as the Mail on Sunday did – the study’s findings are significant for the interrogation of pot potency and use frequency.