US Poison Center Encounters for Psilocybin-Related Exposures: 2013-2022

Given the increasing use of psilocybin-containing substances across a variety of use settings, understanding the potential risks is imperative for informing public health policy, health care providers, and consumers. Poison centers (PCs) receive calls following exposures to potential toxins to support the detection, prevention, and treatment of toxin-related health emergencies. This report assesses trends in PC encounters of psilocybin and a subset of other comparator substances.

A retrospective study of PC encounters documenting exposure to psilocybin, other psychedelic substances (lysergic acid diethylamide, mescaline/peyote, and hallucinogenic plants), or toxic plants and mushrooms from 2013 to 2022 was performed. The primary outcome was the occurrence of psilocybin-related encounters, with and without other coingestants. Psilocybin-related encounters were presented overall and stratified by age groups, and the clinical outcomes were described.

There were 6933 PC encounters for psilocybin-containing substances between 2013 and 2022. PC encounters for psilocybin-containing substances (alone or with coingestants) increased over time-from 477 in 2013 to 1441 in 2022. Psilocybin-related encounters increased over the study period among all age groups (years) and were most common in the 18 to 24 and 25 to 44 year-old age groups. Across all years, the number of psilocybin-related encounters was similar to those for lysergic acid diethylamide and mescaline/peyote, and far lower than those for other mushrooms and toxic plants.

From 2013 to 2022, there was a 3-fold increase in psilocybin-related PC encounters, nearly all of which occurred since 2019. A similar pattern was not observed with other substances. Although the number of encounters remains low, this trend could continue as psilocybin use increases.