Ethnopharmacologic Search for Psychoactive Drugs

In 1967, the first Ethnopharmacologic Search for Psychoactive Drugs symposium was held in San Francisco, California. It was a landmark gathering of international, interdisciplinary specialists — from ethnobotanists to neuroscientists — to share their findings on the use of psychoactive plants in indigenous societies. The findings of the convention were printed in a book with the same title as the gathering, and follow-up meetings were planned for every ten years. The War on Drugs intervened and put a stop to it.

In June 2017, Dennis McKenna, founder of the McKenna Academy, presented a long-awaited 50th anniversary symposium honoring the original ESPD. This edition gathered an international group of specialists to share their perspectives on past, present, and future research in ethnopharmacology. The meeting was co-hosted by Anton Bilton and his Tyringham Initiative, a world-class think-tank for the evolution, expansion and deeper understanding of ‘new-paradigm consciousness.’ Held at the spectacular Tyringham Hall in Britain, the event was also livestreamed, making it accessible to a global audience. View de ESPD50 presentations.

Synergetic Press published a collector’s book set which included the 50th anniversary symposium findings and the first edition book from the 1967 event. More information.


The McKenna Academy of Natural Philosophy presents ESPD55 in 2022, honoring the intentions set in 1967 to hold the symposium on a regular basis, to keep abreast of developments in the field of ethnopharmacology. Under the thoughtful curatorship of Dennis McKenna, President of the McKenna Academy, ESPD55 brings the most esteemed researchers representing findings from the various spheres of life: archaeosphere, ethnosphere, faunasphere, hydrosphere, mycosphere, neurosphere, phytosphere, sociosphere and sonosphere. Topics include huachuma, wilca, coca, kratom, marine sponges, sound and more.

The invited speakers will be hosted at St. Giles House — a spectacular family home that has a 400 year-long rich history at the heart of politics, philosophy and social thought. The McKenna Academy invites the global community to join ESPD55 via the livestream in an engaging online experience. Click here to attend online.

ESPD Symposium Publications

“The discovery of ESPD’s publication changed my life. For me, at least, that book was influential because it provided a cultural context for psychedelics based on traditions older and richer than anything I had encountered in mass media sources.”

Read about Dennis’ personal journey with the first ESPD symposium volume here

ESPD50 Collector’s Box Set

In collaboration with Synergetic Press, the McKenna Academy reprinted the 1967 symposium volume and published the 2017 ESPD conference findings together in a high quality collector’s edition box set that won the esteemed James A. Duke Botanical Literature Award. This popular publication has been reprinted seven times already.

ESPD55 Symposium Volume

The McKenna Academy is again working closely with Synergetic Press to publish the findings of the third edition of ESPD as a stand-alone volume, “ESPD55” in 2023.


Donna Torres, artist of the ESPD50 Collector’s Box Set, offers a commemorative print set for 2022’s ESPD55: the “Visionary Garden Print Set.” As Dennis McKenna’s dear friend, she has crafted this exclusive limited edition of ten portfolios published on the occasion of ESPD55. Each portfolio contains 24 signed and numbered fine art prints of original botanical watercolors.  30% of all sales proceeds will be donated to the McKenna Academy. Enter the magical world of illustrations by Donna Torres, and visit her Visionary Garden here.