Risk for Mania, Bipolar Disease Increased After Hospital-Based Care for Hallucinogens

MONDAY, Dec. 8, 2025 (HealthDay News) -- Hallucinogen use resulting in an emergency department visit or hospitalization is associated with an increased risk for incident mania or bipolar disorder (BD), according to a study published online Dec. 2 in PLOS Medicine.Daniel T. Myran, M.D., M.P.H., from North York General Hospital in Toronto, and colleagues conducted a population-based cohort study of individuals aged 14 to 65 years with no baseline history of BD to examine the risk for incident mania or BD associated with having an emergency department visit or hospitalization involving hallucinogens.The study included 9,311,844 individuals, of whom 7,285 (0.08 percent) had acute care involving hallucinogens. The researchers found that 1.43 percent of individuals had an incident episode of mania requiring acute care within three years of acute care involving hallucinogens compared with 0.06 percent of individuals in the age- and sex-matched general population. After weighting, the risk for incident mania was increased sixfold for acute care for hallucinogens compared with individuals without hallucinogen acute care who had otherwise similar demographic and mental health histories (weighted hazard ratio, 5.97). Increases were also seen for risk for incident BD diagnosis (hazard ratio, 3.75; absolute proportion 2.50 versus 0.11 percent)."There has been a large increase in interest in the use of hallucinogens, often paired with therapy, to treat some mental health disorders. The current study helps highlight that hallucinogen use outside of trial settings may have important risks for a subset of people who use them," Myran said in a statement.One author disclosed ties to the pharmaceutical industry.Abstract/Full Text.Sign up for our weekly HealthDay newsletter