Quantitative Methods for Traditional Chinese Medicine Development

Chapter 11

Population Pharmacokinetics

11.1 Introduction

For a drug product under development, it is of interest to study how the drug moves through the body and the processes of movement such as absorption (A), distribution (D), metabolism (M), and excretion (E) after drug administration. This leads to the study of pharmacokinetics (PK). The key concept of a PK study is to study what the body does to the drug, which is usually characterized by ADME of a drug product after administration. In practice, however, we cannot measure concentrations at the site of action directly. Instead, we can measure concentrations in blood, plasma, or serum that reflect ADME at the site of action. The site of action is defined as the site at which the drug will ...