Factors impacting on drug metabolism

ALAN TALEVI; CAROLINA L. BELLERA

The ADME Encyclopedia. A Comprehensive Guide on Biopharmacy and Pharmacokinetics

Springer Nature

Año: 2022; p. 1 - 7

There are several factors that influence the rate of metabolism of drugs and/or drug biotransformation pathways, thus giving rise to inter- and intra-individual variability in drug metabolism. Inter-individual variability involves differences across individuals of the same species. They have been defined as factors which differ between individuals but are constant throughout the life of an organism [1]; they depend on the genetic makeup of an individual. Genetic variants of metabolizing enzymes can be mentioned in this category. Intra-individual variability refers to factors that vary during the lifetime of an organism, even in the short term [2]. Physiological, pathological, and environmental factors can be included in this category.Factors that impact the expression and/or activity of drug-metabolizing enzymes have often been classified as internal factors, among which species, genetic variants, sex, age, hormones, and disease can be highlighted [3], and external factors, which include dietary factors and other environmental factors (e.g., exposur to therapeutic and recreational drugs, pollutants) [4]. This classification can of course be challenged, as for instance hormone release usually depends of external stimuli, and many diseases have environmental components.