A new study has shown that CBD alters the brain activity of people with psychosis during memory tasks. For the first time, the brains of people diagnosed with psychosis who have taken CBD have been scanned, providing important insight into the areas of the brain that CBD targets. While THC has been linked to an increased risk of psychosis, CBD is potentially beneficial for symptoms of psychosis. It is also possible that biomarkers, such as anandamide in CSF or genetic profiles based on AKT1, COMT or CNR1, may identify individuals at high risk for psychosis or in the early stages of psychosis, who could benefit from CBD or other endocannabinoid-targeted interventions, and may not even need chronic antipsychotic treatment.
Now, a new brain imaging study suggests that a single dose of CBD can reduce symptoms of psychosis by "restoring activity in three areas of the brain." CBD attenuates many of the adverse effects of THC, including psychosis and some elements of cognitive impairment. A 4-week trial in inpatients with acute psychosis without CUD (mean age 30 years) found that 800 mg of CBD had similar efficacy to amisupride in improving psychosis and cognition. CBD may have therapeutic potential for the treatment of psychosis following cannabis use, as well as schizophrenia, possibly with better tolerability than current antipsychotic treatments.
A recent study explored the effect of CBD and placebo in untreated individuals at high risk of developing psychosis, and compared their brain activation by fMRI during a verbal learning task with unmedicated healthy controls. The four small placebo-controlled studies of CBD augmentation in schizophrenia provide mixed and limited support for the ability of CBD added to an antipsychotic to further reduce symptoms of psychosis and improve cognitive impairments. Effects of CBD in Parkinson's psychosisIt appears that the antipsychotic effect of CBD is not limited to patients with schizophrenia. To understand the potential benefit of CBD as a standalone treatment for psychosis, more research is needed.
If replicable, the study offers the first evidence-based explanation of how CBD works in the brain to counteract psychosis, with results that could help generate new treatments. However, studies indicating the potential benefits of cbd in psychosis tend to be observational case and cohort studies, limiting firm conclusions as to CBD's efficacy. Researchers conclude that CBD may partially normalize alterations in brain areas implicated in the development of psychosis. In a follow-up report, the same group studied the effects of up to 1280 mg daily of CBD orally for 4 weeks in 3 patients with treatment-resistant psychosis.
The findings of the effect of CBD using fMRI in the studies reviewed here (6 , which also enrolled young subjects, are similar to recent fMRI studies in young adults, not treated with antipsychotics and at high clinical risk for psychosis.