Hospital-based care for hallucinogens and risk of mania and bipolar disorder: A population-based cohort study.
PLoS medicine December 1, 2025 Daniel T Myran, Rachael MacDonald-Spracklin, Michael Pugliese et al.
Among 9.3 million people in Ontario, those who had an emergency department visit or hospitalization involving hallucinogens faced a 6-fold higher risk of a first episode of mania and a nearly 4-fold higher risk of a new bipolar disorder diagnosis over three years, compared to similar individuals without such acute care. The absolute risk was low: 1.43% of those with hallucinogen-related acute care developed mania versus 0.06% in the general population. The findings apply only to people who required acute care for hallucinogen use, not to most users, and suggest caution for individuals at risk of bipolar disorder.