Mazatec shamans primarily use S. divinorum as a vision-inducing plant. They say it "allows them to travel to heaven and talk to God and the Saints about divination, diagnosis, and healing" (19). Although the plant is reputed to be only "weakly psychotropic," (1) it can produce very powerful visions under the correct circumstances. Rituals are performed to heighten the experience, and darkness and silence are essential for achieving full psychoactivity. Valdés writes "...if the experience becomes too terrifying, it can be readily terminated by saying a few words or producing a light." Dosages of at least 20 pairs of leaves are necessary for psychoactive effects (1). Although its traditional use is as a hallucinogen, the Mazatec shamans only use it when morning glory seeds and Psilocybe mushrooms are unavailable (20). The Mazatecs generally prepare fresh leaves for an infusion by crushing them in water. This apparently forms a microsuspension or emulsion of salvinorin A (and possibly other non-water-soluble psychotropic agents) (1). The dried leaves cannot be used in this manner, as drying changes the chemical composition of the leaves (19).
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