More than half of psychedelic exposures reported to poison centers across the U.S. between 2012 and 2022 had symptoms that required medical treatment or resulted in residual or prolonged symptoms or death, according to a new study from researchers at the University of Colorado School of Medicine.

The paper is published in the journal Annals of Emergency Medicine . As the legal landscape around psychedelic substances shift—like it has in Colorado and Oregon—the need for data persists in understanding real world use and how it's affecting users. "Every person who uses psychedelic substances is different and reacts differently because they alter your perception, mood, and cognition.

One person's desired effect may be another's undesired effect," says Mark Simon, MD, lead author on the study and senior instructor of emergency medicine. "Because of the mechanisms of each of these agents, particularly through serotonergic modulation, some of the complications that we see are either intrinsic to the substance or caused by excess serotonin," he continues. "So it's very different, depending on who gets into these and what their goals are for the psychedelic substance.

" Of nearly 55,000 National Poison Data System cases analyzed by the researchers, 42% had moderate effects that were pronounced or prolonged effects that usually require treatment, 8% had major effects that were life-threatening or resulted in significant residual disability, and 0.5% of cases resulted in death. Appro.