Information seeking and engagement in informal digital environments for substance misuse and recovery: A scoping review

: Informal digital environments play a significant and growing role in substance misuse and recovery, yet research remains fragmented across platforms, populations, and methods. This scoping review aimed to map the landscape of such online environments and to examine how and why individuals engage within them, with particular attention to differences between substance misuse–oriented ( SMO ) and change- and recovery-oriented ( CRO ) contexts. Studies published between 2004 and 2025 were identified in Embase, MEDLINE, Web of Science, Scopus, and PsycInfo. Eligible studies comprised original empirical research on user-driven, organically occurring engagement in informal digital environments and were synthesized across interaction modality, data source, and study orientation. In the 218 included studies, informal digital environments constituted a heterogeneous but internally structured ecosystem, in which general-purpose search engines often served as primary entry points into a dispersed network of platforms including forums, social media, and darknet marketplaces. Across this landscape, a clear distinction emerged between SMO and CRO contexts: SMO engagement was primarily knowledge-oriented, centered on substance effects, dosing, and harm reduction through the exchange and refinement of experiential knowledge, whereas CRO engagement was directed toward behavior change and recovery maintenance, emphasizing self-management and emotional support. Where self-reported data were available, perceived helpfulness across both contexts appeared to depend on the integration of credible, experience-based information with relational affordances. These findings indicate that informal digital environments function as complementary systems that extend access to information and support differentially according to users' relationship to substance misuse. Connecting these environments with accessible, evidence-based resources may strengthen the continuity of care.