Current Scenarios and Future Perspectives of Therapeutic Drug Monitoring in India: A Narrative Review

Therapeutic drug monitoring (TDM) is a precision medicine tool that measures drug concentrations in biological fluids to guide individualized dosing. TDM has evolved into a multidisciplinary approach used across various therapeutic areas. In India, despite a growing clinical need, TDM remains underutilized due to systemic and infrastructural barriers. This narrative review aims to summarize the evolution, current status, analytical approaches, and future prospects of TDM in India and is based on published literature retrieved from databases, including PubMed, Scopus, and Google Scholar, and outlines TDM's utility in optimizing pharmacotherapy for drugs with narrow therapeutic windows or nonlinear pharmacokinetics. It compares analytical methods used for TDM and discusses challenges in the workflow of TDM. Special emphasis is placed on its relevance in children, pregnant women, the elderly, and critically ill patients. It also highlights barriers, including a lack of infrastructure, trained personnel, and standardized guidelines. TDM in India requires policy-level support, integration into national health programs, clinician education, and adoption of point-of-care technologies. Strengthening research in pharmacogenetics can help establish TDM as a cornerstone of individualized therapy.