The use of plants with psychoactive properties by ancient communities has been confirmed in numerous archaeological studies conducted in almost every place on earth. Many tribes used their own characteristic psychoactive potions and, according to researchers, their use fostered the integration of the members of a given community, facilitated their existence in an occupied area and could be of significant importance for its survival. Around the psychoactive plants and toxic secretions of some species of fauna a conglomerate of myths, cults and the properties attributed to them has developed. Permanent traces of their presence remain in both non-material and material culture. The aim of this article is to present the representations of psychoactive substances in the beliefs of ancient communities, their occurrence in myths, rock or sepulchral art, and to discuss the reasons for their use during rituals. The article presents also the main causes of the diffusion of the use of psychoactive plants from the sacred to the profane sphere.