Natural psychoactive substance-related exposures reported to United States poison control centers, 2000-2017.

Context/Objective: To investigate the epidemiology of exposures to psychoactive substances of natural origin in the United States.Methods: Data from the National Poison Data System were retrospectively analyzed to investigate exposures to psychoactive substances of natural origin.Results: From January 1, 2000 through December 31, 2017, there were 67,369 calls to poison control centers in the United States regarding exposures to natural psychoactive substances, equaling an average of 3,743 exposures annually. Individuals >19 years of age (41.4%) and 13-19-year-olds (34.8%) accounted for most exposures with the highest annual rate reported among 13-19-year-olds at 79.4 per million population. The substances most commonly involved were marijuana (46.9%), anticholinergic plants (21.1%), and hallucinogenic mushrooms (15.6%). Kratom, khat, anticholinergic plants, and hallucinogenic mushrooms were the substances with the highest percentages of hospital admission and serious medical outcomes. The overall rate of exposure to natural psychoactive substances per million population increased significantly by 74.1% from 17.6 in 2000 to 30.7 in 2017 (p < 0.001). This increase was driven by a significant 150.0% increase in the rate of exposure to marijuana from 9.9 in 2000 to 24.7 in 2017 (p < 0.001). Despite this overall increase, most substances showed a significant decrease in exposure rate from 2000 to 2017, except for marijuana, nutmeg, and kratom. Kratom demonstrated a significant 4,948.9% increase from 2011 to 2017 and accounted for 8 of the 42 deaths identified in this study.Conclusions: While rates of exposure to most natural psychoactive substances decreased during the 18-year study period, rates for marijuana, nutmeg, and kratom increased significantly.