Abstract
Mushrooms containing hallucinogenic indole compounds are one of the sources of psychoactive substances which are found in nature. These species contain indole derivatives such as for example psilocybin, a naturally occurring hallucinogen. The potential of these compounds for occasioning altered states of consciousness has probably been known by human kind from the very beginning, which is indicated by the ancient findings. The aim of this article is to address the issue of using hallucinogenic mushrooms in purpose of altering consciousness. This work presents a brief report of marks for the ancient use of hallucinogenic mushrooms and other hallucinogens, and discusses the matter of religious experiences facilitated by the use of hallucinogenic indole derivatives. Finally, the controversies over the hallucinogenic substances are taken under consideration.