The Cannabis-Psychosis Spectrum: Clinical Manifestations, Conversion Risk, and Therapeutic Strategies

Valerio Ricci

doi:10.53941/cna.2025.100004

Abstract

Cannabis-induced psychosis (CIP) represents a significant public health concern in the context of increasing global cannabis use and potency. This review synthesizes current evidence on the epidemiology, neurobiological mechanisms, clinical features, and treatment approaches for cannabis-induced psychotic disorders. Recent epidemiological data indicate rising incidence rates of CIP, with estimates ranging from 2.7 to 6.1 per 100,000 person-years in recent studies. The neurobiological mechanisms involve complex interactions between Δ9-tetrahydrocannabinol (THC) and the endocannabinoid system, affecting dopaminergic, GABAergic, and glutamatergic neurotransmission. Clinical manifestations typically include acute onset of paranoid delusions and hallucinations, often distinguishable from primary psychotic disorders by their temporal relationship to cannabis use and relatively preserved insight. Treatment remains challenging, with limited evidence-based guidelines, though second-generation antipsychotics and benzodiazepines show efficacy. The conversion rate to schizophrenia-spectrum disorders ranges from 33–50%, highlighting the importance of early identification and intervention. This review emphasizes the need for improved diagnostic criteria, treatment protocols, and prevention strategies as cannabis legalization continues worldwide.

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