Ayahuasca Admixture Plants: An Uninvestigated Folk Pharmacopoeia

Dennis J. McKenna, PhD



Abstract: Ayahuasca is a psychedelic beverage utilized in the ethnomedical and shamanic practices of numerous indigenous peoples of the Amazon Basin. It has also been adopted as a sacrament in several syncretic churches originating in Brazil. The hallucinogenic properties of ayahuasca derive from the presence of DMT (N,N-dimethyltryptamine), in one or more species of admixture plants, that is rendered orally active by ß-carbolines alkaloids, potent monoamine oxidase inhibitors (MAOI) found in the other key ingredient, the liana Banisteriopsis caapi (Malpighiaceae). Although these ingredients are necessary and sufficient for its visionary properties, in many ethnomedical traditions ayahuasca preparations often include other biodynamically active admixtures. Ayahuasca is, in fact, at the center of a vast and largely unstudied folk pharmacopoeia of associated medicinal plants. This presentation will discuss the botany, chemistry, pharmacological properties, and potential uses of some of these lesser-known species that are utilized by indigenous ayahuasca traditions. The presentation will include an updated overview of some of the admixture species discussed in our 1986 paper on this topic, as well as new species that have come to light since that paper was published.

Dennis McKenna, PhD, received his doctorate in 1984 from the University of British Columbia, where his doctoral research focused on ethnopharmacological investigations of the botany, chemistry, and pharmacology of ayahuasca and oo-koo-hé, two orally-active tryptamine-based hallucinogens used by indigenous peoples in the Northwest Amazon. Dr. McKenna received post-doctoral research fellowships in the Laboratory of Clinical Pharmacology, National Institute of Mental Health, and in the Department of Neurology, Stanford University School of Medicine. He joined Shaman Pharmaceuticals as Director of Ethnopharmacology in 1990, and relocated to Minnesota in 1993 to join the Aveda Corporation as Senior Research Pharmacognosist. He joined the faculty of the Center for Spirituality and Healing at the University of Minnesota in 2001. He is a founding board member of the Heffter Research Institute and serves on the advisory board of non-profit organizations in the fields of ethnobotany and botanical medicines. He was a key organizer and participant in the Hoasca Project, an international biomedical study of ayahuasca used by indigenous people and syncretic religious groups in Brazil. He also recently completed a project funded by the Stanley Medical Research Institute to investigate Amazonian ethnomedicines for the treatment of schizophrenia and cognitive deficits.


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