Psilocybin

Psilocybin (also known as psilocybine) is a psychedelic alkaloid of the tryptamine family, found in psilocybin mushrooms. It is present in hundreds of species of fungi, including those of the genus Psilocybe, such as Psilocybe cubensis and Psilocybe semilanceata, but also reportedly isolated from a dozen or so other genera. Psilocybin mushrooms are commonly called "magic mushrooms" or more simply "shrooms". The intensity and duration of recreational and entheogenic use of psilocybin mushrooms vary depending on species of mushrooms, dosage, individual physiology, and set and setting.