Oregon Ran an Unprecedented Experiment. Now There Are Numbers.
The first study to track safety and mental health outcomes among real clients of a state-regulated psychedelic program was published this week in JAMA Network Open. PIPS helped start the effort behind it.
In 2019 psilocybin was illegal everywhere in the United States. Then Oregon led the way. Voters passed Measure 109 in 2020, creating the first legal state-regulated pathway for adults to take psilocybin. Services launched in 2023 and now more than 20,000 people have used them.
However the measure did not create any mechanism for assessing what happened. There was no funding for finding out how well these services worked or if they were safe.
A group of us set out to close that gap. And this week, the first major results arrived. Safety and Mental Health Outcomes of Oregon State-Regulated Psilocybin Services was published in JAMA Network Open, led by P. Todd Korthuis, MD, MPH, of OHSU, with senior author Adrianne "Adie Rae" Wilson-Poe, PhD, of Legacy Research Institute. Full transparency: I’m (PIPS director Jason Luoma, PhD) a co-author.
What the study found
In this study, our team enrolled 346 people who attended psilocybin sessions at 24 of the 26 Oregon service centers that held active licenses during the study period. Enrollment was from November 2024 through March 2026, with follow-up through June 2026. Participants reported on their mental health before their session and again at one week, one month, and three months afterward. Ninety percent completed the full three-month follow-up, an unusually high retention rate for community-based research.
Serious harms were uncommon. Four participants (1.2%) had adverse behavioral reactions requiring medical attention. No serious physical health events were reported. Seven of the 312 participants who completed three-month follow-up (2.3%) rated their experience as harmful.
Symptoms of depression, anxiety, and PTSD decreased at three months. The share of participants with moderate-to-severe depression fell from 42.2% at baseline to 16.5%; moderate-to-severe anxiety fell from 45.1% to 13.2%.
Well-being and life satisfaction improved. The proportion reporting they were somewhat or very satisfied with life rose from 63.0% at baseline to 82.3% at three months.
People found the experience valuable. At one month, 92.2% felt they had benefited, and 58.6% ranked the session among the ten most meaningful experiences of their lives.
As Korthuis put it, safety looked "very similar to what we've seen with psychedelics in clinical settings.” This is notable because this is emphatically not a clinical setting. This is also not a research setting where participants are typically highly screened and selected very carefully to reduce safety events. This is a broad section of the population, people with a wide range of problems and reasons for seeking services. Facilitators were not required to hold clinical licenses and receive relatively limited training. At the same time, of the 83 facilitators enrolled in the study, more than 70% held at least a master's degree, typically in a mental health field.
What the study does not show
I want to be precise here, because the findings are being widely covered and precision tends to be the first casualty.
This is an observational study with no control group, so we cannot attribute the symptom improvements to psilocybin itself. Expectancy effects, regression to the mean, and the simple fact that people often seek out an intervention when they are at their worst all plausibly contribute. Improvement in an uncontrolled cohort is encouraging; it is not causal evidence.
The sample is also not representative of everyone in Oregon. Participants were disproportionately white, college-educated, and affluent — with 29% reporting incomes above $200,000 — and concentrated around Portland. Three hundred forty-six people is a good sample, but still a small and self-selected slice of the clients served during that window.
The adverse events deserve serious attention. All four serious reactions occurred in people taking psilocybin for the first time, at relatively high doses, with pre-existing serious mental health challenges and prior unsuccessful treatment. Adverse effects ranged from about a day to still ongoing at three months.
That matters because Oregon's mandatory reporting requirement covers adverse reactions occurring within 72 hours of a session. The paper notes that this window means state data underestimates actual safety events. Anything that surfaces weeks or months later falls outside what the state collects. This study is among the first efforts to look past that window, and finding something there is a finding about the surveillance system as much as about psilocybin.
Where this came from
OPEN — the Open Psychedelic Evaluation Nexus — is a community-wide, non-commercial research initiative housed at OHSU and co-directed by Korthuis and Wilson-Poe. It exists because a handful of us in Portland kept arriving at the same conclusion: Oregon was about to run the first experiment of its kind, and no one had a plan to learn anything from it.
I was there when we generated the initial idea for it in 2021. The founding premise was simple and, at the time, not obvious: the right response to an unprecedented policy experiment is measurement. And that measurement should be public, non-commercial, and designed with service centers and facilitators rather than imposed on them.
Participation reflects that approach. Twenty-four of the 26 actively licensed service centers took part, and 90% of participants stayed through three months. Much of this study rests on relationships built over years with people who had no obligation to participate.
What comes next
OPEN holds a five-year, $3.3 million award from the National Institute on Drug Abuse (R01DA060253) to enroll at least 1,600 participants, this time including a comparison group, and focused on people seeking to reduce their substance use. This is the first federally funded work studying the impact of legal psychedelic services delivered in community settings. OPEN has also expanded into Colorado, the second state with regulated psilocybin services.
Oregon could have run this experiment for a decade and produced nothing but anecdotes, leaving the policy debate to whoever told the most compelling story. Instead, three years in, there is a peer-reviewed paper other states can actually use — especially the safety data. And we continue to collect data rapidly. We're currently up to over 670 people in the study, with more enrolling every day.
Soon we will be the largest database of regulated psilocybin administration in the world. We look forward to sharing more results soon.
Read the study and the coverage
The paper: Safety and Mental Health Outcomes of Oregon State-Regulated Psilocybin Services, JAMA Network Open (doi:10.1001/jamanetworkopen.2026.30608)
OHSU: Study finds sustained benefit for people using Oregon psilocybin services
NPR: A real-world study of Oregon's non-medical psilocybin program shows promise
OPB: More than 20,000 people have used legal psilocybin in Oregon. A new study shows how it went.
KOIN 6: OHSU study finds Oregon psilocybin services helped anxiety, depression, PTSD
KPTV 12: OHSU study tracks long-term benefits of magic mushroom therapy
Statesman Journal: Study finds Oregon regulated psilocybin services generally safe
Behavioral Health Business: 95% of Oregon psilocybin study participants saw improvements in depression, PTSD
The Lund Report: More than 20,000 people have used legal psilocybin in Oregon
Healing Maps: Oregon tracks psilocybin safety for three days. The new data found problems at three months
About the Author
Jason Luoma, PhD, is the Director of Research at the Portland Institute for Psychedelic Science (PIPS) and a co-founder of Portland Psychotherapy. He was involved in the early development of OPEN (the Open Psychedelic Evaluation Nexus) and is a co-author on the JAMA Network Open paper. His research focuses on psychedelic-assisted therapy, shame, and Acceptance and Commitment Therapy (ACT). He also hosts the Research Matters Podcast.