Population pharmacokinetics: An overview

Abstract

The pharmacokinetics of a drug refers to how it is handled by the body. This includes absorption, distribution, metabolism and elimination. Pharmacokinetic studies have usually been carried out in small numbers of people, often healthy volunteers. In population pharmacokinetics opportunistic samples are collected from actual patients taking a drug. Population pharmacokinetic studies aim to identify and quantify sources of variability in drug concentration in the patient population. Associations between patient characteristics and differences in pharmacokinetics can then be used to customise pharmacotherapy, such as the safe use of metformin in patients with renal impairment. As multiple samples from one person are not required, a population approach is useful for investigating patient groups that are difficult to study, such as premature infants. Population pharmacokinetics is being increasingly used in drug development. It is particularly useful when it is suspected that the pharmacokinetics of the drug will vary between subgroups of the population.