Abstract

Understanding drug metabolism and pharmacokinetics is essential for safe and effective therapeutic interventions in modern clinical practice. This article aims to provide a comprehensive overview of the principles governing drug disposition in the human body and their application to individualized patient care. The fundamental processes of absorption, distribution, metabolism, and excretion determine drug concentration at target sites and influence therapeutic outcomes. Multiple factors affect drug kinetics, including genetic polymorphisms in drug-metabolizing enzymes and transporters, physiological variables such as age and organ function, pathological states, and drug-drug interactions. Pharmacokinetic modeling and therapeutic drug monitoring have emerged as powerful tools to optimize dosing regimens, particularly for drugs with narrow therapeutic indices or significant interpatient variability. These approaches enable clinicians to achieve target drug concentrations, minimize adverse effects, and improve patient outcomes through evidence-based dose individualization. The integration of pharmacogenomic testing into routine clinical practice represents a paradigm shift toward precision medicine, allowing for prospective identification of patients at risk for altered drug response. Computational tools and population pharmacokinetic models continue to enhance our ability to predict drug behavior across diverse patient populations. Future advances in systems pharmacology, artificial intelligence, and real-time monitoring technologies promise to further refine personalized pharmacotherapy and transform the landscape of clinical drug management.