After Legalization: More Severe and Concerning Cannabis Use in First-Episode Psychosis

As cannabis laws continue to change across the U.S., many families, clinicians, and communities have questions about how legalization may affect young people with serious mental health conditions, including schizophrenia and related psychotic disorders. A recent Letter to the Editor published in Schizophrenia Research draws on analysis conducted by STEP researchers to examine changes in cannabis use patterns among individuals entering care for first-episode psychosis (FEP) in Connecticut before and after recreational cannabis legalization.

STEP researchers analyzed admissions to a specialized early psychosis program in Connecticut from 2014–2025, comparing cannabis use patterns before and after legalization in July 2021.

Key findings included:

• More severe cannabis use after legalization After legalization, a significantly higher proportion of individuals entering care for first-episode psychosis were classified as having moderate to severe cannabis use, while fewer were abstinent.
• More concerning patterns of use Increases were observed in daily cannabis use and solitary use (using alone rather than socially). These patterns are associated with higher risk for cannabis-related problems and cannabis use disorder, particularly among individuals with psychosis and schizophrenia.
• Increases occurred despite a legal age limit In Connecticut, recreational cannabis use is legal only for adults age 21 and older. However, this study included many individuals under age 21, and increases in cannabis use severity were still observed, suggesting that broader changes in availability, social norms, and perceived risk may affect adolescents and young adults with early psychosis even when they are below the legal age.

Cannabis use is strongly linked to poorer outcomes in early psychosis and schizophrenia, including higher risk of symptom relapse, psychiatric hospitalization, and and difficulties in social and occupational activities. We found that these shifts toward more severe and concerning patterns of use occurred among people entering care for first-episode psychosis, a population already at elevated clinical risk.

Importantly, legalization does not mean cannabis is harmless. Shifts in social norms, reduced perception of risk, and increasing availability of high-potency THC products may all contribute to increased risk, particularly for adolescents and young adults during a critical period of brain development.

Our team views these findings as an early warning signal and emphasize the need for continued attention as legalization and commercialization expand.

Moving forward, we believe the findings highlight the importance of:

• Broader monitoring and surveillance of cannabis use patterns and THC potency
• Routine screening and early conversations about cannabis use in individuals at risk for or experiencing psychosis
• Clear, nonjudgmental education and prevention efforts, including outreach to adolescents and families before cannabis use begins
• Public health approaches that account for vulnerability, including personal or family history of schizophrenia or related disorders

Supporting recovery in early psychosis and reducing risk before illness emerges requires a public health approach that keeps pace with changes in cannabis availability, potency, and social norms. Ongoing monitoring, clear education about psychosis risk, and thoughtful prevention efforts are essential as legalization and commercialization continue to evolve.

Purushothaman, D., Tayfur, S. N., Song, Z., Li, F., Corbera, S., Yoviene Sykes, L. A., Riley, S., Ponce Terashima, J., D’Souza, D. C., Tek, C., & Srihari, V. H. (2026). Changes in cannabis use following legalization: Effects in first-episode psychosis (Letter to the Editor). Schizophrenia Research, 290, 86–87. https://doi.org/10.1016/j.schres.2026.02.001

View the article here: https://authors.elsevier.com/a/1mayi3HQGmpwVO