BACKGROUND: Injecting drug users (IDUs) are at increased risk of health problems ranging from injecting-related injuries to blood borne viral infections. Access to primary healthcare (PHC) is often limited for this marginalised group. Many seek care at emergency departments and some require hospital admission due to late presentation. The costs to both the individual and the health system are such that policymakers in some settings have implemented IDU-targeted PHC centres, with a number of models employed. However, there is insufficient evidence on the effectiveness of these centres to inform health service planning. A systematic review examining such interventions is not possible due to the heterogeneous nature of study designs. Nevertheless, an integrative literature review of IDU-targeted PHC may provide useful insights into the range of operational models and strategies to enhance the accessibility and acceptability of these services to the target population. METHODS: Available literature describing the impact of IDU-targeted PHC on health outcomes, cost implications and operational challenges is reviewed. A narrative synthesis was undertaken of material sourced from relevant journal publications, grey literature and policy documents. RESULTS: Several models have proven accessible and acceptable forms of PHC to IDUs, improving the overall healthcare utilisation and health status of this population with consequent savings to the health system due to a reduction in visits to emergency departments and tertiary hospitals. CONCLUSIONS: Although such findings are promising, there remains a dearth of rigorous evaluations of these targeted PHC, with the public health impact of such outlets yet to be systematically documented.