Schizophrenia is a mental disorder that affects a person’s ability to think, feel, and behave clearly. It can cause psychotic episodes, and treatment is usually lifelong and involves antipsychotic medications with toxic side effects.
In 2012, researchers published a study in Translational Psychiatry showing that a CBD isolate can treat schizophrenia as effectively as antipsychotic pharmaceuticals — and with far fewer side effects.
In this study, researchers led by Markus Leweke, MD, of the University of Cologne in Germany recruited 39 people with schizophrenia who were hospitalized for a psychotic episode. Nineteen of the study participants received an antipsychotic medication called amisulpride, while the other 20 were given CBD. After four weeks, both groups significantly improved. There was no difference in psychiatric symptoms between those getting CBD or amisulpride. But those taking CBD had fewer undesirable side effects, such as weight gain and movement disorders, compared to those taking amisulpride. The authors concluded, “These results suggest that cannabidiol is as effective at improving psychotic symptoms as the standard antipsychotic amisulpride.”
CBD appears to provide antipsychotic relief by raising the levels of anandamide, an endogenous cannabinoid compound that acts on the same brain receptors as THC. Curiously, in an earlier study, Daniele Piomelli, director of the Center for the Study of Cannabis at the University of California in Irvine, discovered that people with schizophrenia had anandamide levels that were on average twice as high as mentally healthy people without the disorder. Some scientists speculated that perhaps people with schizophrenia were essentially too high on elevated levels of their own endocannabinoids! But in reality, it seems that the brain actually increases anandamide levels to buffer stress and ease the symptoms of psychosis. The preponderance of evidence suggests that the higher the anandamide levels are in people with schizophrenia, the less severe their symptoms.
Atypical Brain Scans
More recently, in 2020, researchers from Kings College in London used fMRI scans to monitor the brain activity of 13 people with psychosis while they performed a memory test after taking CBD or a placebo and compared it to 16 people without psychosis performing the same test. Those taking placebo had different brain activity in the prefrontal and mediotemporal brain areas associated with memory than the people without psychosis. When participants who had psychosis took one dose of CBD, their brain activity becomes more like their counterparts without the disease.
“Our study provides important insight into which areas of the brain CBD targets. It is the first time research has scanned the brains of people with a diagnosis of psychosis who have taken CBD and, although the sample is small, the results are compelling in that they demonstrate that CBD influences those very areas of the brain that have been shown to have unusual activity in people with psychosis,” said the senior author on the study, Sagnik Bhattacharyya, MD, PhD.
Importantly, in terms of cannabis and safety, one of the biggest health concerns and stigmas about cannabis use has been the idea that it can cause psychosis in vulnerable individuals. This has never been proven. It’s worth noting that a 2012 meta-analysis published in Schizophrenia Bulletin showed that people diagnosed with schizophrenia who use cannabis function better cognitively than people with schizophrenia who do not use cannabis.
An excerpt from The Essential Guide to CBD by the editors of Reader’s Digest and Project CBD. Now available in paperback and as an audiobook.
Recommended Readings
Cannabis & Schizophrenia: A Conspiracy of Causality
A neuroscientist challenges the central fallacy of Reefer Madness.
Cannabis Use Protects the Gut in Schizophrenia
Researchers have found that cannabis users with schizophrenia experienced fewer gut-related issues.
Two Hits for Schizophrenia
After over a century of failing to find a causal link between cannabis use and schizophrenia, proponents of Reefer Madness have had to couch their warnings.