Richard Yensen
Open-knowledge reference entry
Richard Yensen is an American–Panamanian psychologist and psychedelic drug researcher.
He was a research fellow at the Maryland Psychiatric Research Center (MPRC) of the Spring Grove Hospital from 1972 until its closure in 1976. Yensen studied psychedelic-assisted psychotherapy under Stanislav Grof at the MPRC and did his 1975 Ph.D. dissertation on 3,4-methylenedioxyamphetamine (MDA)-assisted psychotherapy through the University of California, Irvine. Along with Claudio Naranjo, he is one of the foremost pioneers of entactogen-assisted psychotherapy.
Yensen has taught at Harvard Medical School, Johns Hopkins University, and the University of Maryland Medical School. His wife is psychiatrist and psychedelic drug researcher Donna Dryer. Yensen developed a novel non-drug shamanistic form of psychotherapy known as perceptual affective therapy. The Yensens are the founders and directors of the Orenda Institute, a psychedelic-assisted therapy organization aimed at continuing the work of centers like the MPRC. In the 1990s, the Yensens attempted to launch government-approved studies of LSD-assisted psychotherapy for treatment of alcoholism and other uses in the United States (FDA IND 3250), but this was ultimately unsuccessful and they soon opted to move to Canada instead.
Subsequently, the Yensens worked in the Canadian phase 2 clinical trials of MDMA-assisted psychotherapy for post-traumatic stress disorder (PTSD) conducted by the Multidisciplinary Association for Psychedelic Studies (MAPS) and Lykos Therapeutics (now Resilient Pharmaceuticals) in the 2010s. They are said to have been leaders of the trial they were involved in.
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