There is evidence that supports the increased risk of developing psychosis or psychotic like symptoms in vulnerable populations after use of cannabis. Cannabis’ main psychoactive component, Δ9-tetrahydrocannabinol (THC), induces acute psychotic effects and cognitive impairment. But there is also evidence to suggest that molecules in the cannabis plant could have an antipsychotic affect.

In this review we are trying to explore the possibilities of cannabis use as a therapeutic agent in mental disorders.

Thorough research of the main databases, and web search engines for relevant studies, using appropriate keywords. We scrutinize them independently, before reaching consensus about appropriateness.

In animal models repeated treatment with cannabis constituent cannabidiol CBD or the atypical antipsychotic clozapine attenuates or reverses the schizophrenia-like behavioral disruption.

In humans there are data that CBD counteracts psychotic symptoms and cognitive impairment associated with cannabis use. Also CBD may lower the risk for developing cannabis use associated psychosis. There are opposite effects of CBD and THC on brain activity patterns in key regions implicated in the pathophysiology of schizophrenia, such as the striatum, hippocampus and prefrontal cortex.

The possible mechanism of action of GBD is not fully clarified, as it may involve anti-inflammatory or neuroprotective properties. These initial clinical studies with CBD treatment of psychotic symptoms argument the potential of CBD as an effective antipsychotic compound. Mechanisms responsible for these effects need to be further investigated.

The authors have not supplied their declaration of competing interest.