A constituent of cannabis known as cannabidiol (CBD) could hold promise as a new class of treatment for psychosis, according to King’s College London research showing significant benefits in a clinical trial. This new research – published in the American Journal of Psychiatry – is the first placebo-controlled trial of CBD in patients with psychosis. Antipsychotic drugs have been the first line treatment for psychosis for the last 60 years. However, they are often only partially effective and can be associated with serious side effects.
88 patients with psychosis received either CBD or placebo for six weeks, alongside their existing antipsychotic medication. Before and after treatment, researchers assessed their level of symptoms, functioning, and cognitive performance, while the patient’s psychiatrist rated their condition overall. Patients treated with CBD had lower levels of psychotic symptoms than those who received a placebo, and were more likely to have been rated as ‘improved’ by their psychiatrist. There were also trends for improvements in cognitive performance and in their level of functioning. Treatment with CBD was not associated with significant side effects.