Dennis McKenna, Ph.D.
Ethnopharmacologist; Author; Founder, McKenna Academy
Ethnopharmacologist who conducted foundational research on ayahuasca pharmacology, brother of Terence McKenna, and founder of the McKenna Academy — a leading voice for rigorous science in psychedelic ethnobotany.
Biography
Dennis McKenna is an ethnopharmacologist, author, and educator whose career has spanned the laboratory, the jungle, and the lecture hall. The younger brother of Terence McKenna, Dennis brought the scientific rigor that complemented his brother's philosophical flair, conducting some of the foundational pharmacological research on ayahuasca that underlies contemporary understanding of the brew's mechanism of action. His doctoral research at the University of British Columbia examined the monoamine oxidase inhibitors in Banisteriopsis caapi that make the DMT in Psychotria viridis orally active — work that established the pharmacological basis for how ayahuasca works.
Dennis co-authored several books with Terence, including The Invisible Landscape (1975) and True Hallucinations, and has continued producing rigorous ethnopharmacological scholarship throughout his career. His book The Brotherhood of the Screaming Abyss (2012) is a detailed memoir of his relationship with Terence and the experiences that shaped both brothers.
In recent years, McKenna founded the McKenna Academy of Natural Philosophy, an online educational institution focused on ethnobotany, consciousness studies, and the rigorous scientific study of psychedelic plants. He serves on the board of the Heffter Research Institute and has been a consistent advocate for research-based approaches to psychedelic policy — insisting that the enthusiasm of the current renaissance be tempered by scientific caution and respect for the indigenous traditions from which many psychedelic practices descend.
He has collaborated extensively with international researchers on ayahuasca studies and has been a steady voice in the psychedelic community for intellectual honesty and methodological rigor.
Organizations
Why They Matter to the LearnShrooms Community
Dennis McKenna provides the scientific counterpoint to his brother Terence's philosophical legacy — grounding the McKenna name in rigorous ethnopharmacology and ensuring that the academic and indigenous dimensions of psychedelic plants receive serious treatment. His pharmacological research on ayahuasca established foundational knowledge that the entire field builds on.
Legal Context
For the legal landscape where Dennis McKenna, Ph.D. operates, see psilocybin laws in Minnesota.