Relationship Between Pharmacokinetics and Pharmacogenomics, and Its Impact on Drug Choice and Dose Regimens

Plasma drug levels can vary due to various factors associated with medications. These factors include: Genetic and epigenetic factors can lead to individual variations in drug metabolism, thereby affecting every stage of the ADME process. For instance, a dysfunctional efflux pump in the enteric membrane can increase the toxicity of certain drugs, alterations in protein binding sites can impact drug distribution, and gene deletions encoding metabolizing enzymes can increase plasma drug concentrations, affecting therapeutic outcomes. Conversely, overexpression of transporters in the apical membrane of renal tubules can rapidly eliminate drugs, thereby decreasing their half-life. In this context, pharmacogenomics plays a crucial role in uncovering variable responses attributed to phenotypic changes resulting from genetic variations. These genetic variations are considered pharmacogenetic biomarkers (Quiñones L, Roco Á, Cayún JP et al (2017) Clinical applications of pharmacogenomics. Rev Med Chil 145:483–500) ( https://www.fda.gov/drugs/science-and-research-drugs/table-pharmacogenomic-biomarkers-drug-labeling ).