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Scientists claim to have discovered why exactly people get paranoid when they smoke pot. Professor Daniel Freeman of the University of Oxford in England led a team in the largest and most in-depth study on the effects of THC, the main ingredient in marijuana.

New York Daily News (USA), 16/07/2014, Meredith Engel

Their findings appear in the journal Schizophrenia Bulletin.  One hundred and twenty-one study participants ages 21-50 with no previous mental health issues were tested on feelings of paranoia, which Freeman described in a release as "excessive thinking that other people are trying to harm us." Two-thirds were injected with THC and one-third was given a placebo. Paranoia tends to happen ‘when we are worried, think negatively about ourselves, and experience unsettling changes in our perceptions,’ Freeman said. When tested, 50% of the participants who got THC injections had paranoid thoughts, compared to 30% who had the placebo. The THC was found to increase anxiety, worry, negative thoughts about oneself and changes in perception, all, which Freeman noted, can lead to paranoia.


Want to know why cannabis makes you paranoid? Largest-ever study of THC reveals how

International Business Times, 17/07/2014, Lydia Smith

Cannabis really can trigger paranoia

The Guardian, 16/07/2014, Daniel Freeman and Jason Freeman

Daniel Freeman of Oxford University, and Jason Freeman, write about the largest ever study of the effects of the main psychoactive component of cannabis, which suggests that it can cause paranoia in vulnerable individuals: ‘Many people use cannabis without adverse effects, and indeed with plenty of very pleasant ones. Moreover, there is evidence that cannabis can bring real medical benefits, for example in alleviating chronic pain. But there is also known to be a link between cannabis and paranoid thoughts…To discover whether cannabis really does cause paranoia in vulnerable individuals, we carried out the largest ever study of the effects of THC (∆9-tetrahydrocannabinol, the drug’s principal psychoactive ingredient)…The results were clear: THC caused paranoid thoughts. Half of those given THC experienced paranoia, compared with 30% of the placebo group: that is, one in five had an increase in paranoia that was directly attributable to the THC…Perhaps most importantly, the research shines a light on the psychological processes underlying paranoia in general. When we worry, think negatively about ourselves and experience perceptual disturbances, it’s much more likely that we will feel needlessly suspicious of others.’


I wasted £30k of benefits getting wasted on weed

The Sun, 16/07/2014, p.19, Robin Perrie

A news in brief piece at the end of another article reports that an Oxford University study has found that cannabis can cause paranoid thoughts.


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