Two studies exist, and both are widely described as something they are not. Here is what each one actually asks.
The short answer
Of the 133 psilocybin trials currently recruiting worldwide, two involve Alzheimer’s disease — and neither tests whether psilocybin treats it. A Johns Hopkins study of 20 people targets depression in patients who have mild cognitive impairment or early Alzheimer’s. A National Institute on Aging study of 200, not yet recruiting, asks whether psilocybin enhances cognitive training. No results have been published from either. The only published human report of psilocybin in advanced dementia is a single case, with no cognitive scales and no imaging, whose authors state that causality cannot be established.
The two studies
Both entries are in our trials registry, pulled from ClinicalTrials.gov on August 31, 2026. The registry record governs; this is a summary of it.
Johns Hopkins University · Early Phase 1 · 20 participants · Recruiting
National Institute on Aging · Phase 2 · 200 participants · Not yet recruiting
The Hopkins study is Early Phase 1 with 20 participants. That designation is not a formality. Early Phase 1 asks whether a thing can be done safely at all — whether the drug can be given to this population, whether they tolerate it, whether the protocol works. It is not designed to detect whether the treatment helps, and 20 people could not answer that question even if it were.
The NIA study is larger and more interesting, and it is still not a dementia treatment trial. It asks whether psilocybin makes cognitive training work better — the drug is an adjunct to a behavioral intervention. It has also not started recruiting, which means the first participant has not been dosed.
So the honest summary of this field is short: two trials, 220 planned participants between them, zero published results, and neither one asking the question that headlines say they are asking.
In 2026 a case report appeared in Frontiers in Neuroscience describing an octogenarian woman with advanced Alzheimer’s who was given high-dose psilocybin-containing mushrooms and showed functional improvements over the following weeks — continence restored after years, improved mobility, more speech.[3] It was covered under headlines about an incredible effect.
The paper is more careful than its coverage, and it is worth reading what the authors actually wrote. There were no standardized cognitive scales, no neuroimaging, no biomarkers and no electrophysiology. There was one patient. The administration happened in private practice with family present, not in a trial.
That second clause is the one that matters most and is left out of every retelling. Advanced dementia fluctuates. People have better days and worse days, better weeks and worse weeks, for reasons nobody can identify. An unblinded observer who expects improvement, watching one person over weeks in a condition that varies on its own, is describing the exact circumstance under which humans reliably see effects that are not there. This is not a criticism of the authors, who said so themselves. It is a criticism of reading a case report as though it were a result.
A case report is a legitimate and useful thing. Its job is to say this is worth looking into, and this one does that job. Its job is not to tell a family what to do, and it cannot.
The case for psychedelics in dementia usually runs like this: psilocybin promotes neuroplasticity, dementia involves loss of neural connections, therefore psilocybin might help. Each step sounds reasonable and the conclusion does not follow.
Psilocybin does appear to produce changes associated with plasticity — dendritic spine growth, altered connectivity — largely in rodents and cell culture. That is a mechanism. A mechanism tells you a treatment is worth testing. It tells you nothing about whether it works, and the history of Alzheimer’s research is substantially a history of mechanisms that were real, plausible, and led to failed trials.
Dementia is also not primarily a plasticity deficit. It involves protein pathology and neuronal death. Promoting plasticity in surviving cells is not obviously the same as addressing that, and the two studies underway do not assume it is — which is precisely why neither is testing psilocybin as a disease treatment.
This pattern is covered more generally on our corrections page: a plausible mechanism, plus an early study, plus an enthusiastic write-up, produces a claim that nobody in the research actually made.
This is the part almost nothing written about psychedelics and dementia addresses, and it is the hardest thing in the field.
Informed consent requires that a person understands what is going to happen to them. Psilocybin produces four to six hours during which someone cannot reliably assess risk, cannot leave, and cannot meaningfully withdraw consent — which is why every legal pathway requires a trained person in the room, as our safety page sets out.
Now apply that to a population defined by impaired cognition. Capacity to consent is the exact faculty in question. Trials handle this with formal capacity assessments and, where capacity is absent, a legally authorized representative — and in the case report above, consent came from the patient’s legal guardian.
Proxy consent is routine and appropriate for many things. Consent by proxy to several hours of profoundly altered consciousness is a harder question than consent by proxy to a blood draw, and it should be argued in public rather than treated as a box that has been ticked. We do not have a settled position on it. We think anyone writing enthusiastically about this application owes readers an acknowledgement that the question exists.
Safety
Transient in healthy trial participants, and a more serious consideration in a population with a higher baseline rate of cardiac and cerebrovascular disease.
Older adults take more prescriptions on average. Lithium and MAOIs are the clearest contraindications; SSRIs and antipsychotics interact in ways set out on our safety page.
A supervised session involves lying down for most of a day, and getting up during it. Fall risk in this age group is not a footnote.
Distinguishing a difficult psychedelic experience from delirium in someone with dementia is genuinely hard, and the management differs.
Both studies exclude on cardiac, psychiatric and medication grounds. Someone excluded from a trial is not thereby a candidate for doing this privately.
Common questions