The number arrived quietly, buried in a federal health survey. Eight million Americans, roughly the population of New York City, used psilocybin in the past year. Not in clinical trials. Not under the guidance of a therapist in an Oregon treatment centre. Just… out there, in homes and parks and wherever people go when they want a few hours of something different. The figure, drawn from the 2024 National Survey on Drug Use and Health, is the first nationally representative estimate of its kind, and it raises a question that researchers are only beginning to know how to ask: what happens when a drug that works beautifully under controlled conditions meets the rather messier conditions of ordinary life?
For years, the data on psilocybin use in the US was frustratingly coarse. National surveys either lumped it in with other hallucinogens or asked only whether someone had ever tried it, which is a bit like asking whether someone has ever eaten a hot dog and using that to understand their diet.
The 2024 NSDUH changed that. For the first time, the survey posed psilocybin-specific questions to more than 58,000 respondents, allowing Kevin Yang, a resident physician in psychiatry at UC San Diego, and his colleagues at NYU to build a genuinely detailed epidemiological picture. What they found was 2.8% past-year prevalence among people aged 12 and older. That is a substantial fraction of the population using a substance that, until very recently, was treated by federal law as having no accepted medical use whatsoever. The landscape has shifted. Oregon launched regulated psilocybin services in 2023; Colorado followed in 2025. The FDA granted psilocybin breakthrough therapy designation for treatment-resistant depression back in 2018, and for major depressive disorder the year after. The clinical world has been moving, and apparently so has everyone else.
“Prior surveys only captured lifetime use, which tells us little about current use patterns,” Yang said. “Someone who tried psilocybin once in college a decade ago and someone using it regularly today look identical in that data. Past-year gives us a much more clinically relevant picture of who is using psilocybin right now and what factors are associated with their use.”
Who Is Actually Using
The demographic breakdown is roughly what you might expect, if slightly more pronounced than previous, cruder estimates suggested. Men outnumbered women by a considerable margin (about 64% of past-year users were male). Use was highest among 18 to 25 year-olds, and dropped sharply after 50, with those over that threshold showing about one-third the odds of use compared to the 35-49 reference group. White respondents had notably higher rates than Black or Hispanic respondents. And college education was strongly associated with use: people with some college or a degree were roughly 2 to 2.5 times more likely to have used psilocybin in the past year than those without a high school diploma. None of this is especially surprising as patterns go. It mirrors the epidemiology of other substance use, and it suggests that access, cultural exposure, and perhaps a certain disposition toward experimentation are doing a lot of work here.
What is more striking is how strongly psilocybin use correlated with use of other substances. Cannabis was by far the strongest predictor: people who used cannabis in the past year had nearly 14 times the adjusted odds of psilocybin use compared to non-users. LSD use was associated with almost 8 times the odds; ketamine with about 6. MDMA, cocaine, prescription stimulant misuse, even alcohol use disorder all showed statistically significant associations. The authors interpret this, reasonably enough, as evidence of a “shared experimentation pattern” rather than psilocybin carving out its own distinct niche. People who use one psychedelic tend, it seems, to use several.
The Depression Puzzle
The finding that has attracted the most interest, and which is perhaps the hardest to interpret, concerns depression. Individuals who had experienced a major depressive episode in the past year had 37% higher adjusted odds of having used psilocybin. That might sound modest next to the cannabis association, but it carries a particular weight given what psilocybin is currently being developed to treat. The clinical trial literature has been quietly building a case for psilocybin-assisted therapy in depression; controlled studies have shown genuinely promising results. Here, though, we are seeing an association between depression and naturalistic, unsupervised use, and the direction is reversed from what you might naively expect.
Earlier epidemiological work, including analyses using older NSDUH data, had actually found that lifetime psilocybin use was associated with decreased odds of past-year major depression, which aligned neatly with the therapeutic narrative. The new finding does not necessarily contradict that. The time frames are just different, in ways that matter enormously. Past-year use places someone’s psilocybin consumption in much closer temporal proximity to their current mental state than lifetime use does. Yang’s team offers several possible explanations: self-medication among people seeking alternatives to conventional treatment, adverse psychological effects from use in unsupervised settings, or shared underlying risk factors that predispose people to both depression and substance experimentation. Probably some mix of all three. Longitudinal studies will be needed to work out the directionality, and they don’t yet exist.
“When psilocybin is used outside of a clinical setting, the risks look very different,” Yang said. “We’ve seen reports of anxiety, paranoia and prolonged psychological distress, and there are also potential interactions with antidepressants that clinicians need to look out for.”
What Clinicians Should Be Asking
The practical upshot, Yang argues, is fairly clear even if the causal story is not. Eight million people is enough that most psychiatrists are going to encounter patients who are using psilocybin outside any formal therapeutic framework, whether or not those patients volunteer the information. The drug interacts with serotonergic medications (the mechanism of action for most antidepressants) in ways that aren’t fully characterised. And the conditions under which naturalistic use tends to happen, variable dosing, unknown product purity, no psychological preparation or support, are pretty much the opposite of what makes controlled clinical use seem safe.
“With 8 million Americans using psilocybin in the past year, this is something that psychiatrists and other clinicians should be asking about, including why patients are using it and what benefits they perceive, as well as being prepared to counsel them on harm reduction and potential risks,” Yang said.
There is something a little vertiginous about the present moment in psychedelic research. Clinical science is carefully building a case for therapeutic use, brick by brick, screening criteria, dosing protocols, trained facilitators, while simultaneously, millions of people are just getting on with it. The survey data captures a world that has already moved past the question of whether psilocybin will become more widely used. It has. What comes next is the harder work of understanding what that actually means for people who are, right now, using it without a therapist or a clinical team or any of the scaffolding that makes the therapy trials look so promising.
Frequently Asked Questions
Is it safe to use psilocybin for depression without a therapist?
The research does not provide a clean answer, but it raises real concerns. Clinical trials showing promising results for depression have relied on careful screening, standardised doses, and psychological support before, during, and after sessions. None of those conditions typically apply to naturalistic use, and the new survey data shows that people with depression who use psilocybin outside clinical settings may face quite different risks, including anxiety, paranoia, and potential interactions with antidepressants. The gap between “works in trials” and “works unsupervised” is wide and not yet well mapped.
Why do people with depression seem more likely to be using psilocybin right now?
The most plausible explanation is some combination of self-medication and shared risk factors, though the data cannot establish which direction the causal arrow points. Some people with depression may be turning to psilocybin because conventional treatments have not worked, which would align with the FDA’s own interest in it for treatment-resistant cases. Longitudinal studies that follow people over time will be needed to untangle this, and those studies do not yet exist.
How does 2.8% past-year psilocybin use compare with what we thought before?
It is higher than older surveys implied, partly because those surveys grouped psilocybin with other hallucinogens and tracked only lifetime use rather than recent use. For context, the survey found that past-year cannabis use was around 22% of the population, but among psilocybin users, cannabis co-use was almost universal: roughly 87% of psilocybin users had also used cannabis in the same year, making it by far the strongest correlate in the study.
What should you tell your doctor if you are using psilocybin?
The researchers’ position is simply: tell them. Psilocybin affects serotonin pathways in ways that can interact with antidepressants, and that interaction profile is not fully understood yet. A clinician who does not know you are using it cannot factor it into prescribing decisions or offer harm reduction guidance. The survey suggests psychiatrists are increasingly likely to have patients in this situation, whether or not those patients are forthcoming about it.
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