Psilocybin for Parkinson's disease rests on one 12-person open-label pilot. No regulator approval appears in the sources reviewed, and it is Schedule I.
Psilocybin has not been shown to help with Parkinson's disease, and psilocybin for Parkinson's disease is investigational only. The evidence base is one 12-person open-label pilot at UCSF. It has been reported twice: a 2025 paper in Neuropsychopharmacology covers safety and symptom scales, and an October 21, 2026 JAMA Psychiatry research letter covers blood markers in 9 of those participants. Neither report had a control group, so neither shows that psilocybin improves or slows the disease. The ClinicalTrials.gov record, the federal Schedule I text and a Compass Pathways company release show no approval for this use.
The UCSF pilot reported tolerability, symptom-scale changes and blood-marker changes, and its design cannot show that psilocybin caused any of them. Federal law lists psilocybin in Schedule I, and Oregon runs a state-regulated program, as read on November 1, 2026. Broader background sits in the psilocybin guide and the psilocybin clinical trials guide.
| Source | What it is | What it reports | What it cannot show |
|---|---|---|---|
| JAMA Psychiatry research letter (October 21, 2026) | A research letter analyzing blood markers from the UCSF pilot (NCT04932434), described by its authors as a nonrandomized, open-label, single-arm trial. | A lower proinflammatory index at all three post-dose time points in the 9 participants with plasma analyzed. GDF-15 lower after each session but not different at 30 days. | Cause and effect. The authors state that the open-label design with no control group limits causal inference. |
| Neuropsychopharmacology pilot paper (2025) | The first report on the same 12-person UCSF cohort, focused on safety and mood symptoms. | No serious adverse events. Ten participants had treatment-emergent adverse events, most often anxiety, nausea and increased blood pressure. No worsening on the MDS-UPDRS. | Whether psilocybin caused the symptom-score changes, because the pilot had no control group. |
| ClinicalTrials.gov record NCT04932434 | The registry entry, sponsored by UCSF, listed as phase 2, single-group, open-label, with no masking. | Actual enrollment of 12 at one site (UCSF), a start date of August 15, 2021 and completion on December 31, 2024. | Approval or proof of benefit. The record lists the design, outcomes and status of one completed pilot. |
| 21 CFR 1308.11, Schedule I(d) | The federal list of Schedule I controlled substances. | Psilocybin at entry (29), DEA code 7437, and psilocyn at entry (30), code 7438, with no exemption listed. | Medical use, approval or any state exemption. The text is a scheduling list and says nothing about research or Parkinson's disease. |
| Compass Pathways release (April 24, 2026) | A company press release about COMP360, its synthetic psilocybin formulation, in treatment-resistant depression. | FDA granted a rolling new drug application (NDA) review request and selected COMP360 for the Commissioner's National Priority Voucher program. | Anything about Parkinson's disease. The release covers depression only and refers to treatment "if approved." |
| Oregon Health Authority psilocybin services page | A state agency page for the Oregon Psilocybin Services program. | The program implements Ballot Measure 109, codified in the Oregon Revised Statutes (ORS) as ORS 475A, with licensed service centers and facilitators. | Whether the program is open to a given person with Parkinson's disease. The page does not describe the services as medical treatment and does not address federal law. |
No source reviewed for this page shows that psilocybin helps with Parkinson's disease. The research is one open-label pilot (registered as phase 2) of 12 adults with mild-to-moderate Parkinson's disease and mood dysfunction, run at UCSF. The JAMA Psychiatry letter and the Neuropsychopharmacology paper report that one cohort twice, so they do not count as two independent studies.
The 2025 Neuropsychopharmacology paper by Ellen R. Bradley and colleagues reported tolerability and lower depression and anxiety scores.
Neither report can show that psilocybin caused these changes. The JAMA Psychiatry authors state that the open-label design with no control group limits causal inference, and the symptom scores in the 2025 paper come from that same uncontrolled design.
No source reviewed for this page tests whether psilocybin slows or modifies Parkinson's disease, or whether lower inflammatory markers explain any symptom change. The 2025 paper, as summarized on PubMed, says psilocybin therapy in Parkinson's disease "warrants further investigation," and the letter's authors describe their blood data as initial.
News coverage reported the result. NPR's October 21, 2026 report, by Will Stone, quoted Bradley calling the study "an initial biological signal to investigate" and senior author Aoife O'Donovan saying the blood findings need confirmation in follow-up studies before definitive claims. Charles Nichols of LSU Health Sciences Center, who was not involved, told NPR that earlier inflammation-biomarker studies of psilocybin were mostly in healthy volunteers.
Psilocybin for Parkinson's disease is unapproved, investigational and federally Schedule I, as read on November 1, 2026. State programs exist, but no source reviewed for this page ties any of them to Parkinson's disease care.
Approved: No source reviewed for this page reports approval of psilocybin by the Food and Drug Administration (FDA) for any condition, or by any regulator for Parkinson's disease or its mood symptoms. The FDA step in the sources reviewed is in the Compass Pathways release of April 24, 2026, which says FDA granted a rolling NDA review request and a National Priority Voucher for COMP360 in treatment-resistant depression. That release refers to treatment "if approved" and does not concern Parkinson's disease, a point the psilocybin for depression guide covers from the depression side.
Investigational: Psilocybin for Parkinson's disease exists only as research. The evidence is the 12-person UCSF pilot listed on ClinicalTrials.gov as NCT04932434, phase 2, single-group and open-label, with a status of completed. Open psilocybin studies can be searched with the clinical trial finder.
State-regulated: The Oregon Health Authority says its Psilocybin Services program "implements Ballot Measure 109 (now codified as ORS 475A)" through licensed service centers and licensed facilitators. Its page does not describe those services as medical treatment or address federal law. The psilocybin legal states and countries map lists other state programs. No state program is FDA-approved treatment for Parkinson's disease. No source reviewed for this page establishes whether a state program is open to a given person with Parkinson's disease or what it can lawfully do for that person.
Federal Schedule I: Psilocybin appears in Schedule I(d) of 21 CFR 1308.11 at entry (29), Drug Enforcement Administration (DEA) code 7437, with psilocyn at entry (30), code 7438, and neither entry lists an exemption. A state program does not change that federal status, and a lawyer decides how these rules apply to one person. The legal status by state tool, the guide to whether mushrooms are legal and the guide to which psychedelics are legal in the US cover the wider map.
The October 21, 2026 JAMA Psychiatry research letter reported that a proinflammatory blood index was lower after psilocybin at every time point measured, in 9 of the 12 pilot participants. The index averaged five markers: IL-6, IL-8, tumor necrosis factor alpha (TNF-alpha), interferon gamma (IFN-gamma) and CRP. Silo Pharma Inc and an anonymous donor funded the work, and the letter states the funders had no role in its design, conduct, analysis or manuscript decisions.
Under the registered protocol, participants received oral synthetic psilocybin at 10 mg and then 25 mg about two weeks apart, with blood drawn at baseline, one day after each session and 30 days after the second session. Those amounts describe a supervised research protocol and are not dosing guidance. In the 9 participants with plasma analyzed, the index was lower one day after the 10 mg session (standardized mean difference, or SMD, -0.72, adjusted P value .003). It was also lower one day after the 25 mg session (SMD -0.60, adjusted P value .02) and 30 days after it (SMD -0.62, adjusted P value .047).
The individual markers did not all move together in those 9 participants. IL-6 (SMD -0.50, adjusted P value .01), IL-8 (SMD -0.51, adjusted P value .01) and CRP (SMD -0.37, adjusted P value .047) were lower after the 10 mg session only. TNF-alpha and IFN-gamma were not different after false-discovery-rate adjustment. Interleukin-10 (IL-10) was higher after the 10 mg session only (SMD 0.25, adjusted P value .03).
The letter also measured two markers of mitochondrial stress in the same 9 participants. GDF-15 was lower after both sessions (SMD -0.65 and -0.54, each with an adjusted P value of .048) but not different at 30 days. Fibroblast growth factor 21 (FGF-21) was higher after each session without passing statistical testing. The authors note that GDF-15 and FGF-21 are sensitive but not specific markers of mitochondrial stress.
The authors list the limits of these results. They state that the open-label design with no control group limits causal inference, that the sample was small, and that false positives remain possible despite multiple-comparison correction. They also name placebo effects, regression to the mean, clinical heterogeneity, and changes in stress or sleep as possible explanations, and they call for follow-up studies.
The 2025 Neuropsychopharmacology paper reported no serious adverse events among the 12 participants, no medical interventions needed to manage drug effects and no worsening of psychosis. Ten of the 12 had treatment-emergent adverse events, most often anxiety, nausea and increased blood pressure.
Each of the two psilocybin sessions was given with psychotherapy. As with the blood-marker letter, these session amounts describe the supervised protocol and are not dosing guidance.
On symptom scales, the paper reported no worsening on the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS). Scores improved through one month after the second session: Part I by 13.8, Part II by 7.5 and Part III by 4.6. Depression scores on the Montgomery-Åsberg Depression Rating Scale (MADRS) fell by 9.3 and anxiety scores on the Hamilton Anxiety Rating Scale (HAM-A) fell by 3.8, with both changes persisting at three months.
These are open-label results with no control group, so they cannot be attributed to psilocybin. The JAMA Psychiatry authors name placebo effects and regression to the mean among the explanations an uncontrolled design cannot rule out, and the same design produced these symptom scores. People on antidepressants can find general interaction background in the psilocybin and SSRI guide, and any medicine change belongs with the prescriber.
The UCSF pilot enrolled adults aged 40 to 75 with mild-to-moderate Parkinson's disease, defined as Hoehn and Yahr stages 1 to 3, who also had mood dysfunction. The 2025 paper describes the 12 participants as having depression, anxiety or both, with a mean age of 63.2 and 5 women in the group.
People outside those bounds were not studied. That includes adults younger than 40 or older than 75, people with Parkinson's disease past Hoehn and Yahr stage 3, and people with Parkinson's disease who had no depression or anxiety. The published results say nothing about those groups.
The registry record lists one site, UCSF, with a start date of August 15, 2021, primary and study completion on December 31, 2024, actual enrollment of 12 and a status of completed. Its registered primary outcomes include the MDS-UPDRS, the Columbia Suicide Severity Rating Scale (C-SSRS), psychosis measures, caregiver distress, adverse events and retention.
The sources reviewed for this page report no results from other sites or larger groups. Read the ClinicalTrials.gov record for NCT04932434 for its registered eligibility rules, and take questions about Parkinson's medicines to the treating neurologist. The psychedelic medication safety guide and the medication safety checker give general interaction background.
Psilocybin has no established benefit for Parkinson's disease. It is investigational only, approved by no regulator in the sources reviewed, and a Schedule I substance under federal law as read on November 1, 2026.
That answer rests on published reports of one UCSF cohort of 12, reported twice (Neuropsychopharmacology in 2025 and JAMA Psychiatry in 2026). It also rests on the ClinicalTrials.gov record NCT04932434, the text of 21 CFR 1308.11, the Oregon Health Authority program page and the Compass Pathways release of April 24, 2026. This page reports published research only. The answer applies to people with Parkinson's disease, their caregivers and clinicians reading about this pilot.
The answer would change with randomized controlled data showing a benefit, an FDA action for a Parkinson's disease indication, or a DEA rescheduling of psilocybin. None of the three appears in the sources reviewed for this page.
Talk to the treating neurologist before changing any Parkinson's medicine, and search the clinical trial finder for current psilocybin Parkinson's disease studies. The ClinicalTrials.gov record NCT04932434 shows how the completed pilot was designed.
Not established. The published research reviewed for this page is one open-label pilot of 12 people at UCSF, registered as phase 2 and reported in 2025 and again in October 2026. It reported tolerability and a lower proinflammatory blood index in the 9 participants with plasma analyzed, but with no control group it cannot show that psilocybin improves or slows Parkinson's disease.
No. No source reviewed for this page reports approval of psilocybin for Parkinson's disease by the FDA or any other regulator, as read on November 1, 2026. The Compass Pathways release of April 24, 2026 concerns COMP360 for treatment-resistant depression and refers to treatment "if approved."
Psilocybin is a Schedule I controlled substance under federal law, listed at 21 CFR 1308.11 entry (29), DEA code 7437, with no exemption listed. Oregon runs a licensed Psilocybin Services program under Ballot Measure 109 (ORS 475A), but the Oregon Health Authority page does not describe it as medical treatment, and a state program does not change federal Schedule I status. No source reviewed establishes whether a state program is open to a given person with Parkinson's disease, and a lawyer answers that for an individual.
No source reviewed for this page reports that psilocybin cures, slows or modifies Parkinson's disease. The UCSF pilot measured safety, symptom scales and blood markers in 12 people without a control group. Its authors describe the data as initial and say the results support further study.
The October 21, 2026 JAMA Psychiatry research letter reported a lower proinflammatory blood index at all three post-dose time points in 9 of 12 pilot participants. That included 30 days after the second session (standardized mean difference -0.62, adjusted P value .047). IL-6, IL-8 and CRP were lower after the 10 mg session only (a registered study protocol amount, not dosing guidance). GDF-15 was lower after each session but not different at 30 days, and the authors state that the open-label design limits causal inference.
No source reviewed for this page reports on dopamine levels or dopamine depletion. The UCSF pilot reports on inflammatory and mitochondrial-stress blood markers and on symptom scales such as the MDS-UPDRS, MADRS and HAM-A. A neurologist can address dopamine and medication questions for an individual patient.
The UCSF pilot enrolled only adults aged 40 to 75 with mild-to-moderate Parkinson's disease (Hoehn and Yahr stages 1 to 3) who also had depression, anxiety or both. People outside those groups were not studied, including younger and older adults, people past Hoehn and Yahr stage 3, and people with Parkinson's disease without mood symptoms.
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