This paper is the first thorough analysis of takini, a hallucinogen used by the shamans of several peoples in Suriname, French Guiana, and the region east of the Para in Brazil. The drug is contained in the latex of the Brosimum acutifolium tree, and until now, its psychotropic properties appeared inconsistent with the more general medicinal uses of the tree in the surrounding region. Our chemical and botanical studies reveal that the active ingredient of takini is bufotenine; and that this compound is only contained in the subspecies Brosimum acutifolium Huber subsp. acutifolium C.C. Berg that is found in the same area of the eastern Guianas.