One Dose Of Magic Mushrooms Cut Severe Depression In 50% Of Patients. The NHS Trial Just Proved It.
The first publicly funded randomised controlled trial of psilocybin for depression in the United Kingdom has produced results that researchers at King's College London describe as very promising, finding that a single 25mg dose of psilocybin, the active compound in magic mushrooms, produced significant improvements in treatment-resistant depression compared to a placebo, with effects holding through six weeks of follow-up. The study, known as PsiDeR and published in Nature Medicine on August 6, 2026, recruited 60 patients with treatment-resistant depression, meaning each had already failed to respond to at least two prior treatments. Half received a single dose of psilocybin alongside psychological support from trained guides. The other half received a true placebo with the same support. At three weeks, 43 percent of the psilocybin group had met the threshold for treatment response compared to 3 percent of the placebo group. By six weeks, 50 percent of the psilocybin group had responded and 40 percent had met remission criteria, meaning their symptoms had dropped low enough that they no longer met clinical criteria for depression. The placebo group remained at 3 percent throughout.
The trial was funded by the National Institute for Health and Care Research and delivered by South London and Maudsley NHS Foundation Trust in partnership with King's College London, making it the first time psilocybin therapy has been studied in a public healthcare NHS setting with government funding and a true placebo control. Notably, the trial set no upper limit on treatment resistance: participants included people who had already failed many different types of treatment, making the population more representative of patients who might actually be offered psilocybin if it were approved for clinical use. Lead investigator Professor James Rucker said people who received psilocybin were much more likely to improve than those who received placebo, while acknowledging that individual responses varied and that some of the difference will be due to non-drug factors such as expectation. A participant described the experience in a BBC Radio 4 interview as getting very intense, involving emotional visions of family members they had lost, followed by a feeling that the treatment helped them understand their depression more and feel their feelings. Professor Ben Carter, the study's lead clinical trial methodologist, called the findings exciting and said they replicate commercially funded studies showing the considerable potential of psychedelics as a class of medication, while noting that confirmatory trials are still needed before they could be made available on the NHS.
