In this May 4, 2018 photo, foreign tourists look for souvenirs and ayahuasca in the Pucallpa market, deep in the Amazonian jungle of Peru. The tourist trail to the spiritual use of ayahuasca by Westerners took off with the publication in 1963 of “The Yage Letters”, in which beatnik poet Allen Ginsberg described feeling like a “snake vomiting out the universe” after trying ayahuasca in the Colombian rainforest. (Photo by Martin Mejia/AP Photo)
