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Long before modern laboratory testing, indigenous cultures used these substances to treat psychological and physical ailments. The Aztecs used psilocybin mushrooms as medicine, while Andean cults consumed mescaline-rich San Pedro cacti thousands of years ago. Archaeologists have found a ritual bundle thousands of years old in a Bolivian cave that contains traces of DMT (a potent hallucinogenic found in plants). They also found 5,000-year-old peyote buttons from Texas.