This article traces a map of the social control of drugs through the politics of space, according to the Foucaultian concept of "heterotopia." Firstly, a brief genealogy of the use of psychotropic substances in different times and cultures is described, up to the introduction of the prohibitionist paradigm. Attention is paid to the way in which power has marked, separated and enclosed certain rituals and uses of pleasure in physical and symbolic sites. The itinerary is focused on the Spanish context to establish a dialogue between the various policies of space that have come into being and have overlapped in the construction and management of a problem which has been rendered an object to the gazes, mechanics and discourses of the medical, legal, and social fields. In this way, the intersections between the liminal spaces of drug use and the harm reduction paradigm are analyzed, including therapeutic strategies with prescribed drugs, from methadone programs to the new heroin programs.