Registered clinical studies investigating psychedelic drugs for psychiatric disorders.

Abstract

Psychedelics are a hallucinogenic class of psychoactive drugs with the primary effect of activating non-ordinary states of consciousness. Due to the positive preliminary findings of these drugs in the treatment of psychiatric disorders, the number of registered clinical studies has risen significantly. In this paper, clinical studies registered on clinicaltrials.gov that evaluate the treatment of any psychiatric disorder with psychedelics (excluding ketamine) are summarized and analyzed. 70 registered studies were identified from a clinicaltrials.gov search on December 3, 2020. The majority of studies aim to investigate methylenedioxymethamphetamine (MDMA) (45.7%) and psilocybin (41.4%). Studies evaluating ayahuasca, lysergic acid diethylamide (LSD), ibogaine hydrochloride, salvia divinorum, 5-MeO-DMT and DMT fumarate were less common at 1.4%, 4.2%, 2.8%, 1.4%, 1.4% and 1.4% of total registered studies, respectively. Most of the studies on MDMA, psilocybin, ayahuasca and salvia divinorum investigated their therapeutic effect on post-traumatic stress disorder (PTSD) and major depressive disorder (MDD). LSD was investigated for MDD, anxiety, and severe somatic disorders and ibogaine hydrochloride was investigated for substance and alcohol use disorders. 5-MeO-DMT and DMT fumarate were both investigated for MDD. Only 21/70 registered studies had published results with the majority not yet completed. In view of the large number of ongoing studies investigating psychedelics, it is imperative that these studies are considered by researchers and stakeholders in deciding the most relevant research priorities for future proposed studies.

In the evidence

This study is part of the evidence base for 4 syntheses in the library. Here is how each one recorded it.

• State of the evidence: Ayahuasca for depression ?Unclear

  As of December 2020, 70 registered trials were investigating psychedelics for psychiatric disorders, with ayahuasca representing a small fraction and only 21 studies having published results.

  Synthesized September 21, 2026

• State of the evidence: DMT for depression ?Unclear

  As of December 2020, 70 registered trials were investigating psychedelics for psychiatric disorders, with DMT and 5-MeO-DMT among the less common compounds studied for MDD and only 21 studies having published results.

  Synthesized September 21, 2026

• State of the evidence: LSD for depression ?Unclear

  As of December 2020, 70 registered clinical trials investigate psychedelics for psychiatric disorders, with LSD investigated for MDD, anxiety, and severe somatic disorders, but only 21 studies had published results.

  Synthesized September 21, 2026

• State of the evidence: MDMA for PTSD ?Unclear

  As of December 2020, 70 registered trials were investigating psychedelics for psychiatric disorders, mostly MDMA and psilocybin for PTSD and major depressive disorder, but only 21 had published results.

  Synthesized September 21, 2026

Comparable studies

Other narrative reviews on DMT for depression, most cited first.