Earlier cannabis initiation among people with recent-onset psychosis is associated with more severe positive symptoms and greater gray matter volume in a cerebellar network previously linked to schizophrenia. This cerebellar volume increase correlates with lower volume in an insula-temporal-frontal network also implicated in schizophrenia. The findings suggest that early cannabis use may alter the developmental trajectory of specific brain networks, increasing later psychosis risk.
Psychedelic drugs that activate 5-HT2A receptors are known for treating psychiatric disorders, but growing evidence shows they also modulate immune responses by inhibiting pro-inflammatory cytokine release. In vivo studies demonstrate that psychedelics like (R)-DOI reduce inflammation in animal models of asthma and other inflammatory diseases. Clinical studies with psilocybin show effects on circulating cytokine levels, supporting translation from animal models to humans. These findings highlight the promise of targeting inflammation therapeutically. Recent research has identified compounds that maintain therapeutic potential without causing psychedelic effects, termed PIPI drugs (Psychedelic drug Informed but Psychedelic experience Inactive), offering new avenues for treating mental health and inflammation.