The historical opposition to psychedelic research and implications for credibility in psychiatry.

Psychedelics are a group of psychoactive substances that alter consciousness and produce marked shifts in sensory perception, cognition, and mood. Although psychedelics have been used by indigenous communities for centuries, they have only recently been investigated as an adjunctive therapeutic tool in psychotherapy. Since the early twentieth century, psychedelic-assisted psychotherapy has been explored for the treatment of several neuropsychiatric conditions characterized by rigid thought patterns and treatment resistance. However, this rapidly emerging field of neuroscience has evolved alongside opposition in several areas, including the affiliation with mid-twentieth century counterculture movements, media sensationalization, legislative restriction, and scientific criticisms such as "breaking the blind" and "excessive enthusiasm." This perspective article explores the historical opposition to psychedelic research and the implications for the credibility of the field. In the midst of psychedelic drug policy reform, drawing lessons from historical events will contribute to clinical research efforts in psychiatry.