A review of emerging therapeutic potential of psychedelic drugs in the treatment of psychiatric illnesses

Abstract

Though there was initial interest in the use of psychedelic drugs for psychiatric treatment, bad outcomes and subsequent passage of the Substance Act of 1970, which placed psychedelic drugs in the Schedule I category, significantly limited potential progress. More recently, however, there has been renewal in interest and promise of psychedelic research. The purpose of this review is to highlight contemporary human studies on the use of select psychedelic drugs, such as psilocybin, LSD, MDMA and ayahuasca, in the treatment of various psychiatric illnesses, including but not limited to treatment-resistant depression, post-traumatic stress disorder, end-of-life anxiety, and substance use disorders. The safety and efficacy as reported from human and animal studies will also be discussed. Accumulated research to date has suggested the potential for psychedelics to emerge as breakthrough therapies for psychiatric conditions refractory to conventional treatments. However, given the unique history and high potential for misuse with popular distribution, special care and considerations must be undertaken to safeguard their use as viable medical treatments rather than drugs of abuse.

In the evidence

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

• State of the evidence: MDMA for anxiety ↑Supports

  Reports that accumulated research suggests psychedelics including MDMA may become breakthrough therapies for psychiatric conditions refractory to conventional treatment, including end-of-life anxiety, while requiring safeguards against misuse.

  Synthesized October 22, 2026

Comparable studies

Other narrative reviews on MDMA for anxiety, most cited first.