Zuardi AW, Crippa JA, Hallak JE, Bhattacharyya S, Atakan Z, Martin-Santos R, McGuire PK, Guimarães FS.
Δ(9)-tetrahydrocannabinol (Δ(9)-THC) is the main compound of the
Cannabis Sativa responsible for most of the effects of the plant.
Another major constituent is cannabidiol (CBD), formerly regarded to be
devoid of pharmacological activity. However, laboratory rodents and
human studies have shown that this cannabinoid is able to prevent
psychotic-like symptoms induced by high doses of Δ(9)- THC. Subsequent
studies have demonstrated that CBD has antipsychotic effects as observed
using animal models and in healthy volunteers. Thus, this article
provides a critical review of the research evaluating antipsychotic
potential of this cannabinoid. CBD appears to have pharmacological
profile similar to that of atypical antipsychotic drugs as seem using
behavioral and neurochemical techniques in animal models. Additionally,
CBD prevented human experimental psychosis and was effective in open
case reports and clinical trials in patients with schizophrenia with a
remarkable safety profile. Moreover, fMRI results strongly suggest that
the antipsychotic effects of CBD in relation to the psychotomimetic
effects of Δ(9)-THC involve the striatum and temporal cortex that have
been traditionally associated with psychosis. Although the mechanisms of
the antipsychotic properties are still not fully understood, we propose
a hypothesis that could have a heuristic value to inspire new studies.
These results support the idea that CBD may be a future therapeutic
option in psychosis, in general and in schizophrenia, in particular.