Anthropologist Wade Davis’s wonderfully vivid description of the effects of Amazonian hallucinogenic plants from page 216 of his fantastic book, One River:
In the case of yagé, some twenty one admixtures have been identified to date. Two of these are of particular interest. Psychotria viridis is a shrub in the coffee family. Chagopranga is Diplopterys cabrerana, a forest liana closely related to yagé. Unlike yagé, both of these plants contain tryptamines, powerful psychoactive compounds that when smoked or snuffed induce a very rapid, intense intoxication of short duration marked by astonishing visual imagery.
The sensation is rather like being shot out of a barrel lined with baroque paintings and landing on a sea of electricity.
Link to more information about One River.