New UW study links cannabis users with psychotic disorders to higher rates of health problems

OG article by Noel Gasca

January 30, 2026

A University of Washington study analyzing surveys from 4,144 Washington cannabis users (2020–2023) revealed higher health issues among those with psychotic disorders like schizophrenia. These users reported elevated physical symptoms attributed to cannabis, including nausea, vomiting, dizziness, heart problems, and cannabis hyperemesis syndrome. Nearly 21% experienced cannabis-related nausea/vomiting, compared to 5% without mental health diagnoses. Mental health impacts were also greater: 18% reported recent hallucinations or psychotic episodes (vs. 3% without diagnoses), plus increased panic attacks and general mental health problems. Lead researcher Beatriz Carlini highlighted these community-level insights from self-reported online surveys, which reach beyond clinical populations but lack medical record verification. While valuable for broader patterns, the study calls for diversified data from doctors, records, and treated patients. Researchers created an online guide for clinicians discussing cannabis effects and recommend warning labels on products for users with psychotic disorders. The findings underscore complex risks for vulnerable groups and the need for ongoing research into cannabis's full health impacts.