Medical Marijuana: Cannabis Extract CBD Used to Successfully Treat Psychosis

A single dose of cannabidiol (CBD), a chemical found in the cannabis plant, could help to ease symptoms of psychosis, according to a small study.

CBD is a compound present in cannabis plants that is already used to treat rare childhood epilepsy. Unlike the psychoactive ingredient tetrahydrocannabinol (THC), it doesn't make users feel high.

Mental disorders such as schizophrenia, bipolar disorder, as well as severe anxiety and depression can trigger psychosis. The condition can make a person feel as though they have lost touch with reality, according to the National Institute of Mental Health. They might also experience aural and visual hallucinations, struggle to speak coherently, and behave inappropriately. Doctors might prescribe such patients with antipsychotic drugs.

The paper published in the journal JAMA Psychiatry is thought to be the first to show why cannabidiol might help those with psychotic symptoms. Last year, the same researchers at King's College London, in the U.K., conducted a trial that concluded cannabidiol could target psychosis. In their latest piece of research, the team investigated how this approach may work.

Stock image of cannabis leafs. A former Playboy model is relying on cannabis oil to treat her brain tumor. Getty Images

Dr. Sagnik Bhattacharyya, reader of translational neuroscience and psychiatry at King's College London and co-author of the study, told Newsweek: "The mainstay of current treatment for people with psychosis are drugs that target the dopamine chemical signaling system in the brain.

"These drugs were first discovered in the 1950s and no new types of drugs to treat psychosis have emerged since then. While they have been very useful in treating psychosis, they do not work well in a large section of people.

"Our results have started unraveling the brain mechanisms of action of a drug (cannabidiol) that does not seem to have any direct effect on the dopamine signaling system."

In their small study, the researchers enlisted 33 young people who were experiencing psychotic symptoms, but had not yet been diagnosed with the condition, as well as 19 healthy participants who acted as a control. Of the participants enduring psychosis, 16 were given cannabis oil, while the remainder were assigned a placebo.

Related: FDA approves psychedelic magic mushrooms ingredient psilocybin for depression trial

To document their brain, the participants were scanned with an MRI machine while they completed a memory task intended to use the parts of the brain associated with psychosis.

The results showed individuals dosed with cannabidiol had less severe abnormal brain activity than those assigned the placebo. That's probably because cannabidiol switches brain activity to normal levels, the authors of the study believe.

But cannabis used outside of a controlled clinical environment doesn't ease psychosis, the researchers warned. In fact, researchers at King's College London previously found strong associations between THC and psychosis. CBD, however, seems to have the opposite effect.

Next, researchers will oversee the first large-scale trial to test cannabidiol on young people at high risk of developing psychosis.

Bhattacharyya commented: "One of the main advantages of cannabidiol is that it is very safe and seems to be very well tolerated, making it in some ways an ideal treatment. Therefore, if cannabidiol were to prove effective in large scale clinical trials, it would be a welcome addition to treatments currently available."

This article has been updated with comment from Dr. Sagnik Bhattacharyya.