September 16, 2026
As interest and access to psychedelic substances continue to evolve across the United States, new research from Denver Health’s Rocky Mountain Poison & Drug Safety (RMPDS) provides a closer look at how these substances are being used and the experiences people report.
The 2025 National Survey Investigating Hallucinogenic Trends (NSIHT) estimated that 5.3% of U.S. adults 18 or older, or approximately 13.9 million people, used at least one of 13 types of substances reported on from the survey.
Psilocybin was the most commonly used psychedelic substance, with an estimated 7.8 million adults, or 2.9%, using it in the last year, up from 2.1% in 2024. MDMA was estimated to be used by 4.2 million adults, prescription ketamine or esketamine by 3.3 million and LSD by 2.6 million.
These patterns of use were accompanied by both perceived benefits and potential harms. Half (49.9%) of adults who used psilocybin reported that their mental health improved following use, though mental health improvement seems to vary by which substance was used. However, among people who used the substances within the previous three months, side effects were reported by 72.6% of those using psilocybin, 77.2% of those using MDMA, 82.1% of those using LSD and 68.8% of those using prescription ketamine or esketamine.
Use also differed across demographic and geographic groups. Overall use was highest among younger adults and males. Prevalence was highest in the Pacific census division at 6.9% and lowest in the East South Central census division at 3.3%.
“Nearly 14 million adults reported using at least one of the substances included in our survey in 2025, with psilocybin being the most commonly reported,” said Kate Reynolds, MPH, director of Research at Rocky Mountain Poison & Drug Safety. “At the same time, a substantial number of people reported benefits and side effects, highlighting the range of experiences people may experience with psychedelic use.”
RMPDS researchers say the findings underscore the importance of healthcare providers asking patients specifically about psychedelic substances such as psilocybin, LSD, MDMA and ketamine. Grouping all substances under the term “psychedelics” can overlook important differences in how they are used and the effects people experience.
“These findings reinforce the need for continued research into the real-world use of psychedelics,” Reynolds said. “As access and public interest grow, communities need evidence that can help distinguish potential therapeutic applications from unintended health effects and identify opportunities to reduce harm.”
Researchers emphasize that the survey’s findings on perceived mental health improvements reflect participants’ experiences and do not establish that psychedelic substances are effective treatments for mental health conditions. Those data are being collected in other clinical trials.
