Cannabidiol (CBD), a key compound of medical marijuana could potentially provide a new type of treatment for mental health patients with psychosis.
CBD is widely known to have therapeutic benefits for several illnesses, including multiple sclerosis.
A new medical trial led by scientists at King’s College London’s Institute of Psychiatry, Psychology & Neuroscience conducted a placebo-controlled trial of CBD in patients with psychosis and published their findings in the American Journal of Psychiatry. The trial found that this compound can ease symptoms of psychosis like hallucinations and hearing voices.
The study, offers new insights into this drug, with promise of something to ease psychosis with no serious side effects. The main ingredient in cannabis is delta-9-tetrahydrocannabinol (THC). It can induce paranoia and anxiety and hallucinations. But its second major compound, CBD, which does not cause a high, has a completely opposite effect.
Volunteers in the trial, which involved 88 patients, received CBD or a placebo for six weeks on top of their traditional antipsychotic medication. Before and after, the scientists assessed symptoms, functioning and cognitive performance, and the patients’ psychiatrists rated their overall condition overall. Patients treated with CBD had lower levels of psychotic symptoms than those who received a placebo, the scientists concluded. They were also more likely to have been rated as ‘improved’ by their psychiatrist.
“The study indicated that CBD may be effective in psychosis: patients treated with CBD showed a significant reduction in symptoms, and their treating psychiatrists rated them as having improved overall,” said professor Philip McGuire, who co-led the trial.
He said conventional drugs acted by blocking biological receptors for mood-altering chemical dopamine. “However, dopamine is not the only neurotransmitter whose function is altered in psychosis, and in some patients dopamine function may be relatively normal,” he added. “We need new classes of treatment that target different neurotransmitter systems.”
“Although it is still unclear exactly how CBD works, it acts in a different way to antipsychotic medication, and thus could represent a new class of treatment.
“Moreover, CBD was not associated with significant side effects. This is also potentially important, as patients may be reluctant to take antipsychotic medication because of concerns about side effects.”
In a preliminary report last month, the World Health Organization’s Expert Committee on Drug Dependence concluded that clinical and pre-clinical studies of CBD show no evidence of a potential for users to abuse the drug or suffer any harms. The experts also found that CBD has several medical benefits, particularly for treating epilepsy. In its conclusion, the ECDD declared that the current data “does not justify scheduling of cannabidiol.”
"Saying it should not be scheduled for international control means that it should not be prohibited, at the international level, to produce and supply it for specific purposes, such as medical treatment and research, given that WHO has not so far seen evidence of potential for abuse or harm from cannabidiol," a spokesperson wrote. "As to what is legal or illegal, that comes under national law, so it is up to countries to decide."