Background and aimsInjection drug useâassociated bacterial and fungal infections are increasingly common, and social contexts shape individualsâ injecting practices and treatment experiences. We sought to synthesize qualitative studies of socialâstructural factors influencing incidence and treatment of injectingârelated infections.MethodsWe searched PubMed, EMBASE, Scopus, CINAHL and PsycINFO from 1âJanuary 2000 to 18âFebruary 2021. Informed by Rhodesâ ârisk environmentâ framework, we performed thematic synthesis in three stages: (1) lineâbyâline coding; (2) organizing codes into descriptive themes, reflecting interpretations of study authors; and (3) consolidating descriptive themes into conceptual categories to identify higherâorder analytical themes.ResultsWe screened 4841 abstracts and included 26 qualitative studies on experiences of injectingârelated bacterial and fungal infections. We identified six descriptive themes organized into two analytical themes. The first analytical theme, social production of risk, considered macroâenvironmental influences. Four descriptive themes highlighted pathways through which this occurs: (1) unregulated drug supply, leading to poor drug quality and solubility; (2) unsafe spaces, influenced by policing practices and insecure housing; (3) healthâcare policies and practices, leading to negative experiences that discourage access to care; and (4) restrictions on harm reduction programmes, including structural barriers to effective service provision. The second analytical theme, practices of care among people who use drugs, addressed protective strategies that people employ within infection risk environments. Associated descriptive themes were: (5) mutual care, including assistedâinjecting and sharing sterile equipment; and (6) selfâcare, including vein health and selfâtreatment. Within constraining risk environments, some protective strategies for bacterial infections precipitated other health risks (e.g. HIV transmission).ConclusionsInjectingârelated bacterial and fungal infections are shaped by modifiable socialâstructural factors, including poor quality unregulated drugs, criminalization and policing enforcement, insufficient housing, limited harm reduction services and harmful healthâcare practices. People who inject drugs navigate these barriers while attempting to protect themselves and their community.