Education / Research

Can Psilocybin Help With Depression? What the Studies Say

Last reviewed

Depression is the best-studied area in psilocybin research, and the one where the results are strongest so far. That is still a long way from settled. This page walks through the main trials, what each one can and cannot tell us, and what is still unknown.

Every study below links to its source so you can read it yourself.

What the trials found

Randomized trials

Fifteen trials, a large average effect

A living review, which updates as new trials arrive, pooled 15 randomized trials with 801 people. On average, depression scores fell meaningfully more in the groups given psilocybin than in comparison groups. In the main analysis (12 trials, 585 people) the effect size was 0.90, which researchers usually call large.

Worth knowing

The authors flag that many of the included studies were small or at risk of bias, and say the large pooled effect should be interpreted with caution. Because the experience is noticeable, people in these trials can often tell what they were given, which can inflate results. The trials paired psilocybin with psychological support, so the result describes psilocybin plus support, not psilocybin alone.

Randomized trials

One session, still there six weeks later

In a randomized trial of 104 adults with major depression, one psilocybin session with psychological support was compared with an active placebo, a substance chosen so that people would feel something. Improvement showed up quickly and was still there at the six-week check. No serious treatment-related adverse events occurred. Headache, nausea, and visual effects were common on the day.

Worth knowing

The experience is noticeable, so people may have known which one they received, and the trial did not test whether they could tell. Follow-up was six weeks, the group was mostly white and higher income, and the trial was funded by the nonprofit that develops the drug.

Treatment-resistant depression

Treatment-resistant depression means depression that has not improved after several standard treatments. It is the group the largest psilocybin trials have focused on, and it is one of the fastest-growing searches in this area.

Randomized trials

Treatment-resistant depression: one session helped at three weeks, not by twelve

In a phase 2, double-blind, randomized trial, 233 adults with treatment-resistant depression had one psilocybin session with psychological support, at a high dose, an intermediate dose, or a very low control dose. Three weeks later the high-dose group had improved by 6.6 more points on a standard depression scale than the control group. The intermediate dose did not differ significantly from control. Overall, 77 percent of people reported side effects such as headache, nausea, and dizziness, and suicidal thoughts or behavior, or self-injury, occurred in all three groups.

Worth knowing

The main result was at three weeks, and a sustained response at 12 weeks was not supported. The control was a very low dose, not an inert placebo, and participants were not asked to guess what they had received, so expectation cannot be ruled out. The trial was funded by the maker of the drug. Everyone was supervised, so it says little about use outside a clinic. Suicidal thoughts and behavior occurred in every group, which the authors note is common in this population, and they call for close monitoring.

A company, Compass Pathways, has announced results from two larger phase 3 trials of its psilocybin product in treatment-resistant depression and has said it plans to apply to the US FDA. We could not find peer-reviewed papers for those trials, so we treat the announcements as news, not evidence, and will update this page when the papers appear.

What to keep in mind

In these trials a clinical team screened everyone first, prepared them, stayed with them through the session, and followed up afterward. The results describe that whole package, not a substance taken on its own.

The experience is hard to disguise, so people may have known which group they were in. That can inflate the results, and it is a known concern in this field. The people in the trials were also mostly not representative of everyone with depression, and follow-up was weeks, not years.

So the fair summary is that the early evidence is real and worth taking seriously, and that larger, longer, more diverse trials are still needed.

If you are struggling

This page describes research. It is not medical advice, and it is not a substitute for care. Depression is treatable, and a doctor or therapist can help you find what fits. Please do not stop or change a prescription on your own.

If you are thinking about harming yourself or are in crisis, call or text 988 in the US to reach the Suicide and Crisis Lifeline, any time.

Keep reading

This page is for adults 21 and older. It summarizes published research for education only. It is not medical or legal advice, and it makes no claim that any product sold by Luna treats, cures, prevents, or helps any condition. Laws about these mushrooms vary by place, and you are responsible for knowing yours.

Research moves quickly. We last checked this page against its sources on , and we will correct it if we get something wrong.