One Psilocybin Dose Beat Niacin for Depression at Six Weeks. At One Year, the Gap Was Within Chance
Fifty-three percent of the psilocybin group was in remission at six weeks versus 6 percent on niacin. At one year it was 53 percent versus 41 percent, and nearly every psilocybin recipient had guessed their assignment.
By Eli Okafor, Health & Wellness
· 4 min read · Updated
Key Takeaways
- •In a 35-person Swedish randomized trial, 53 percent of the psilocybin group was in remission at day 42, against 6 percent on niacin.
- •At day 365 remission was 53 percent versus 41 percent, and the clinician-rated difference between groups was no longer significant.
- •94 percent of psilocybin recipients correctly guessed their assignment, which weakens confidence in the early gap.
- •Two psilocybin participants had severe anxiety lasting weeks and needed medical attention.
What is actually known comes from one small trial. In a Swedish randomized study of 35 adults with moderate to severe depression, a single 25 mg dose of psilocybin brought faster improvement than a 100 mg dose of niacin, and by one year the two groups no longer differed by more than chance would explain. The trial appeared in JAMA Network Open on May 15, 2026, and coverage of it is circulating again this week.
The study was led by Hampus Yngwe, a doctoral student and consultant psychiatrist at Karolinska Institutet. It enrolled adults aged 20 to 65 with recurrent major depressive disorder, a current episode, and a score of at least 22 on the 60-point Montgomery-Asberg Depression Rating Scale, or MADRS. Participants were recruited through social media and online ads. None had used psychedelics before, and none was taking antidepressants or in psychotherapy at entry.
The short answer
A single 25 mg psilocybin dose cut depression scores faster than niacin in a 35-person Swedish trial, and 53 percent of the psilocybin group was in remission at six weeks versus 6 percent. By one year it was 53 percent versus 41 percent, a gap that could be chance. Nearly all psilocybin recipients knew their assignment, so the early advantage is less certain than it looks.
What changed in the first six weeks
Seventeen people got psilocybin and 18 got niacin, a vitamin that causes flushing and served as an active placebo so participants had a physical sensation to feel. Both groups also had five psychotherapeutic support sessions over 17 days. On the primary measure, clinician-rated MADRS at day 8, scores fell by an average of 9.7 points in the psilocybin group and 2.4 points in the niacin group, according to HealthDay's account of the paper. PsyPost put the between-group difference at about 7 points.
53% vs 6%
in remission at day 42, psilocybin vs niacin
17 and 18 participants. At day 365 the figures were 53% vs 41%, a difference the authors say could be due to chance.
Self-reported symptoms separated early, from day 2, and the psilocybin group stayed ahead through day 102. The clinician-rated advantage held at days 15 and 42.
What happened by one year
Remission in the psilocybin group was still 53 percent at day 365. Remission in the niacin group climbed from 12 percent to 41 percent over the same year, and the clinician-rated difference between groups was no longer significant. The authors suggest the rise reflects how depression behaves, including spontaneous remission. Antidepressant starts during follow-up were close: 6 in the psilocybin group and 7 in the niacin group.
That second number is the base rate that matters. Four in ten people on a vitamin pill plus support sessions were in remission a year later.
Why the blinding problem matters
Ninety-four percent of the people who received psilocybin correctly guessed that they had, and clinicians guessed correctly for most participants too. When people know they got the drug, expectation can shape self-reported improvement, and interview-based ratings can drift with it. PsyPost's summary of the paper's limitations adds that social media recruitment may have drawn people with high hopes for treatment. With 35 participants, the trial could only detect large effects.
Risks and what comes next
Most side effects were headache, anxiety and hallucinations, and they were temporary. Two people in the psilocybin group had severe anxiety that lasted weeks after dosing and needed medical attention. Johan Lundberg, a professor of clinical neuroscience at Karolinska and the senior researcher, said in the institute's news release that the treatment is not risk-free and that some patients may need extra support.
Yngwe said the long-term effects are uncertain. The authors call for further work on repeated dosing or adjunctive treatment. The team also plans to analyze brain scans and blood and spinal fluid samples collected before and after dosing. "We therefore want to investigate whether psilocybin alters synaptic density in the brain," Yngwe said.
The bottom line
Solid, within this one trial: psilocybin plus five support sessions outperformed niacin plus the same sessions at day 8 and day 42 on clinician ratings. Preliminary: everything beyond that. This is one small trial at one center, I found no replication in the coverage reviewed, the blind failed, and the niacin group caught up by one year. The evidence is thin on whether the drug changes the course of depression or speeds a recovery that a large share of people reach anyway.
The full paper was not available to me, so the figures here come from two accounts of it, PsyPost and HealthDay, which agree with each other. None of the coverage I reviewed names a funder.
- psilocybin
- depression
- JAMA Network Open
- Karolinska Institutet
- clinical trial
Sources
- 01A single dose of psilocybin eased depression within days, but its edge over placebo faded within a year, PsyPostpsypost.org
- 02Single psilocybin dose provides rapid relief from depression, small clinical trial finds, HealthDay via Powers Healthpowershealth.org
- 03Short-Term and Late-Term Effects of Psilocybin on Symptoms in Major Depression: A Randomized Clinical Trial, JAMA Network Open (PubMed record)pubmed.ncbi.nlm.nih.gov
Corrections
No corrections have been made to this article.
About the reporter
Health & Wellness Reporter, Trestlewire
I come from a health-policy and medical-reporting background, and I want to say the same thing up front that I say in nearly every piece I write: I am not a physician, and nothing I write is medical advice. My job is to report on health accurately — to explain what a study found, what it didn't, and what a reader can actually do with that — not to practice medicine from a keyboard.
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