Table 1 Age-dependent factors that influence the pharmacokinetics in children and adolescents
Pharmacokinetic parameter | Influencing factors |
|---|---|
Absorption | Gastrointestinal function (for example gastric emptying and intestinal motility; hydrochloric acid production, bile acid secretion, intestinal and body length) |
Distribution | Body composition (for example extra-cellular and total-body water space, volume of distribution, changes in the composition and amount of circulating plasma proteins, body fat) Regional blood flow Organ perfusion Permeability of cell membranes Acid-base balance Passive diffusion of drugs into the central nervous system |
Metabolism | Metabolic capacity (for example liver size, activity of drug-metabolising phase I and II enzymes such as P-450 cytochromes and glucuronosyltransferase) |
Excretion | Renal function |