Cannabis-associated psychotic symptoms and neurocognitive effects at high risk psychosis patients

The epidemiological evidence clearly demonstrates that heavy cannabis use, particularly of high potency types, or of synthetic cannabinoids, increases the risk of psychotic disorders, especially in those who start their use in their early teen years. Genetic predisposition to schizophrenia does not explain the proportion of cannabis use in the general population or in patients; this undermines the argument that those individuals who develop psychotic disorders following cannabis use were destined to develop schizophrenia anyway and their cannabis use was simply an epiphenomenon of this predisposition. Preliminary evidence from candidate gene studies also suggested that certain individuals were especially vulnerable to cannabis-induced psychosis due to the fact that they possess risk alleles in DRD2 and AKT1 genes.