Welcome to the world of biopharmaceutics and pharmacokinetics! This book aims to provide a comprehensive understanding of the principles, concepts, and applications of these intertwined disciplines that play a vital role in modern pharmaceutical sciences. Biopharmaceutics explores the relationship between the formulation of a drug product and the pharmacokinetic behavior it exhibits in the human body. It delves into the intricate processes of drug absorption, distribution, metabolism, and excretion, unraveling the factors that influence the drug's fate and therapeutic effectiveness. Pharmacokinetics, on the other hand, focuses on the quantitative study of the drug's movement in the body, employing mathematical models to predict drug concentrations at different sites and time points. The field of biopharmaceutics and pharmacokinetics has witnessed remarkable advancements in recent years, driven by technological innovations, the emergence of novel drug delivery systems, and a deeper understanding of physiological processes. This book is designed to be a comprehensive guide for students, researchers, and professionals seeking to navigate the complexities of this rapidly evolving field.Throughout the chapters, we delve into the fundamental principles underlying drug absorption, distribution, metabolism, and excretion, providing a solid foundation for understanding drug kinetics. We explore various mathematical models and equations used in pharmacokinetic analysis, enabling readers to quantitatively evaluate drug behavior in different physiological compartments. In addition to the theoretical aspects, this book also emphasizes practical applications. We discuss the development and optimization of drug formulations, the influence of physiological and pathological factors on drug disposition, and the application of pharmacokinetic principles in individualizing drug therapy and designing dosage regimens. Real-world examples and case studies are integrated to illustrate the relevance and impact of biopharmaceutics and pharmacokinetics in clinical practice. I would like to express my sincere gratitude to all the contributors who have shared their expertise and insights in the creation of this book. Their invaluable contributions have helped shape a comprehensive resource that reflects the latest advancements in the field.