Study: Cannabis used for pain and anxiety linked to higher risk of paranoia

The largest study to date on cannabis use shows that people who start smoking to combat pain, anxiety or depression are at a higher risk of developing paranoia, compared to those who use recreationally. The research, led by specialists from the Institute of Psychiatry, Psychology and Neuroscience (IoPPN) at King's College London, was published in the journal BMJ Mental Health.

• Link between trauma and vulnerability

The study complements previous analyses that have highlighted a link between childhood trauma and higher levels of paranoia in cannabis users. This context could explain why some people, especially those with traumatic experiences, are more vulnerable to the psychoactive effects of the plant.

• The difference between medical and recreational use

The results of the Cannabis&Me survey, which surveyed 3,389 current and former cannabis users in London with no history of clinical psychosis, showed a stark contrast: Those who started using to manage pain, anxiety, depression or minor psychotic symptoms had higher paranoia scores; those who said they started using for fun or curiosity had much lower scores.

Currently, medicinal cannabis is available in the UK through the National Health Service (NHS) only for selected patients - for example, children with rare forms of severe epilepsy, people with multiple sclerosis or cancer patients suffering from severe nausea caused by chemotherapy. However, private clinics also offer cannabis treatments for other conditions, including chronic pain or mental health disorders. However, recreational use remains illegal. Cannabis is classified as a class B drug, and its possession, cultivation, distribution or sale are punishable by law.

• Experts warn: THC, a risk factor

Specialists point out that people who use cannabis to treat their health problems tend to use higher doses and products with a high content of THC (tetrahydrocannabinol) - the main psychoactive compound of the plant. This increases the likelihood of adverse effects such as paranoia.

Researchers emphasize that although cannabis has potential benefits for certain conditions, its use must be carefully monitored, especially among people with a history of trauma or mental health problems. The results of the study could contribute to improving public health policies and a better understanding of how the motivations for use influence the risks associated with cannabis use.