Psilocybin and psilocin are potent psychoactive tryptamine compounds with a rich history of shamanistic use. Psilocybe species of mushroom can be found to grow naturally near-globally and have existed at least as long as humans. The psychoactivity of psilocybin mushrooms was known by the Aztecs, who considered their effects to be of religious significance (the mushrooms became known as ‘God’s Flesh’).
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