It has been found that the acute effects of cannabis can be modified by the subject's level of vulnerability to psychosis. Recent studies using fMRI in young adults without prior antipsychotic treatment and with a high risk of psychosis have yielded similar results. Placebo was used to increase antipsychotics in some studies (58, 61-6), while another compared CBD with amisulpride in seriously ill patients who had not taken antipsychotics for at least 3 days (59, 60).The exact pharmacological mechanisms behind the antipsychotic action of CBD are still not fully understood, as this compound appears to interact with neurotransmitter systems in various ways. To provide an updated review, as well as a critical and detailed analysis of the literature, including studies on CBD and THC taken together, a critical review of research methods, the quality of the research and the frankness of the evidence from each study (5) was conducted, focusing on randomization controlled trials (RCTs) as they provide the highest level of evidence. CBD has been found to partially normalize activations in certain regions of the brain, as well as reduce functional hyperconnectivity between the hippocampus and the striatal body.
In addition to relieving anxiety, CBD has also been found to reduce psychotic symptoms commonly induced by THC. Other potential explanations for its antipsychotic action include its ability to increase neurogenesis and hippocampal neuroprotection; its interaction with 5HT1A, GPR55 and TRPV1 receptors; and its antioxidant and anti-inflammatory effects. In one study, Boggs et al. (6) conducted a parallel, double-blind, 6-week group RCT of 300 mg of CBD twice a day, compared to a placebo. It is noteworthy that studies that found a positive effect on increasing CBD (62-6) did not exclude participants with CUD or those currently using cannabis, nor did they carefully measure cannabis consumption throughout the study period. Surprisingly, CBD has been found to be safe even at high doses and has no serious adverse consequences.
However, higher THC content may be sufficient to cause deterioration and intoxication, particularly in the pediatric population.