psilocybin /sī′lōsī″bin, -sib″in/ , a psychedelic drug and an active ingredient of various Mexican hallucinogenic mushrooms of the genus Psilocybe mexicana. It can produce altered states of mood and consciousness and has no acceptable medical use in the United States. Psilocybin is controlled under Schedule I of the Controlled Substances Act of 1970, which bans the prescription of psilocybin and numerous other drugs and allows their procurement and use only for special research projects authorized by the Drug Enforcement Administration of the U.S. Department of Justice.
