This article deals with the use of psychoactive substances in rituals. In addition to tackling the issue of defining drugs and related terms (psychedelics, hallucinogens, entheogens), the article presents maps of altered states of consciousness related to their use, as well as types of psychedelic experience and factors affecting them, concepts of religion/faith and rituals that define the conceptual framework, and shows that the phenomenon has not been treated adequately in the Croatian context. The article considers the historical and contemporary context of their use in medicine, shamanism, magic, religion, as well as in spirituality, art, psychiatry, psychotherapy, counterculture and youth subculture. Moreover, the discussion presents the geography, botanical and cultural scope of entheogen usage, as well as the similarities and differences in psychoactive substance use and in the responses of social institutions. Some of the social problems and consequences that the regulation of their use presents to the modern society are highlighted, including restrictive legislation, the “war on drugs”, preventing scientific research of the phenomenon, as well as violations of human rights and religious freedoms. The article concludes by emphasizing the research potential of the topic and the challenges it presents.