Outpatient Parenteral Antimicrobial Therapy in Asia: Evolution, Models, and Challenges over the Past Decade-A...

Background: Outpatient Parenteral Antimicrobial Therapy (OPAT) has long been established as a safe and cost-effective alternative to inpatient care in Western healthcare systems. In contrast, its implementation across Asia has historically been fragmented and unstructured. A landmark multinational survey in 2017 identified OPAT in Asia as a "missed opportunity," citing the lack of systematic oversight, standardized protocols, and outcome monitoring systems. Methods: This narrative review examines the evolution of OPAT in Asia over the past decade, synthesizing evidence from regional studies, national policies, and implementation models. Results: The findings demonstrate a clear shift from ad hoc infusion practices toward structured, multidisciplinary OPAT programs in several healthcare systems. These systems increasingly integrate antimicrobial stewardship principles, dedicated care teams, and reimbursement mechanisms. In parallel, innovative models, including hospital-at-home services and elastomeric pump-based continuous infusion, have expanded treatment feasibility while enabling the use of narrower-spectrum antibiotics. Despite these advances, substantial heterogeneity persists. Key barriers include the absence of unified national guidelines, limited monitoring infrastructure, workforce constraints, and regulatory restrictions in certain settings. Resource-limited regions continue to face challenges related to financing, laboratory capacity, and digital health integration. Conclusions: Overall, OPAT in Asia is transitioning from an underrecognized and inconsistently delivered service to an increasingly structured component of infectious disease care. Future priorities include standardized governance, integration with antimicrobial stewardship programs, sustainable reimbursement, digital outcome monitoring, and region-specific evidence on antimicrobial stability and safety.