Method
Where every figure comes from
One source, one method, and the parts of it that are a judgement call are stated here rather than left for a reader to discover.
The source
ClinicalTrials.gov, and nothing else
Every trial on this site comes from the US National Library of Medicine’s registry through its public API. Registration is a legal requirement for most interventional trials in the United States and a condition of publication at most serious journals, which makes it the closest thing to a complete record that exists.
Titles, summaries, eligibility criteria, outcomes, sponsors and site lists are reproduced as sponsors wrote them. We do not rewrite them, and no page here contains a description of a trial written by us or by a model.
Classification
How a trial earns a substance tag
The registry’s own search is generous, so a keyword match is not enough. A trial is tagged for a substance only where that substance is named in its title, summary or interventions, and each tag carries a guard against the abbreviation colliding with something else in medicine. These are not hypothetical:
| Collision | Excluded because |
|---|---|
| LSD / low starch diet | A coeliac trial abbreviates its intervention to LSD. |
| LSD / long slow distance | An exercise training study does the same. |
| LSD / least significant difference | A statistical term that appears in trial summaries. |
| DMT / disease-modifying therapy | Every multiple sclerosis trial ever run uses this abbreviation, sometimes without spelling it out. |
| DMT / dynamic motion therapy | A bone density study using a vibration platform. |
| DMT / psilocybin | Psilocybin’s own chemical name contains dimethyltryptamine, so a psilocybin trial would otherwise be tagged twice. |
The one editorial judgement
Why ketamine is filtered and nothing else is
Ketamine belongs here: esketamine is an approved psychiatric medicine and it is the precedent for everything else on this site. But ketamine is also one of the world’s most common surgical anaesthetics, and 1,184 of its 1,702 registry entries are anaesthesia and postoperative pain.
Including those would make a site about psychedelic psychiatry three-quarters a site about surgery. So ketamine is admitted only where the indication is psychiatric. No other substance is filtered this way, because no other substance has a second career.
Limits
What this method cannot tell you
- Registration is not completion. A registered trial may never start, may stop early, or may never report. Roughly a fifth of the trials here have results posted.
- Status is only as fresh as the last data build. A trial can close to entry the day after a build, and the registry record is always more current than this site.
- Trials outside the United States are included where they are registered here, but non-US registries are not consulted, so international coverage is incomplete.
- A trial is listed under its lead sponsor only. Collaborators, funders and the sites actually doing the work are not counted as sponsors.
- An indication with a single trial gets no page: one study is too thin a basis for one, and the trial itself serves the reader better.
Substances covered: LSD, Psilocybin, MDMA, Ketamine, DMT, Ibogaine, Mescaline. Data build 2026-08-25, from ClinicalTrials.gov API v2. LSD.com reports registered clinical research. It is not medical advice, it is not a recommendation to take any substance, and trial listings are not endorsements. Talk to a clinician.