Hofmann 's employer Sandoz marketed and sold pure psilocybin to physicians and clinicians worldwide for use in psychedelic psychotherapy .
In 1959 , the Swiss chemist Albert Hofmann isolated the active principle psilocybin from the mushroom Psilocybe mexicana .
Albert Hofmann 's employer Sandoz marketed and sold pure psilocybin to physicians and clinicians worldwide for use in psychedelic psychotherapy .
In 1959 , the Swiss chemist Albert Hofmann isolated the active principle psilocybin from the mushroom Psilocybe mexicana .