Purpose: The purpose of this paper is to discuss what kinds of messages about the risks of polydrug use are mediated in YouTube video blogs and on what kinds of norms and values do the vloggers base these messages. Design/methodology/approach: The data consist of 12 YouTube videos where vloggers share their own experiences of the risks and harms of polydrug use. In the analysis, the actantial model of Greimas’ theory of structural semiotics was applied. Findings: Two main types of videos were identified – sobriety and controlled use – where polydrug use has different meanings. In sobriety videos, polydrug use is presented as the heavy use of multiple substances. In the videos dealing with controlled use, polydrug use is taken as the combining of certain substances. Whereas the sobriety videos emphasized total abstinence from all substances due to their destructiveness, the videos about controlled use emphasized risk awareness when combining substances. Despite modern digital media and a new generation operating in this space, the messages of the risks of polydrug use mainly repeat those of familiar discourses. Originality/value: This paper offers an analytical insight into the ways in which the risks of polydrug use are conceptualized in a YouTube context that is increasingly gaining a foothold among the youth. Greimas’ actantial model offers a fruitful tool to find semiotic meanings that hide under the surface. The model has not been applied in previous drug research.