Abstract
Changes in maternal physiology during pregnancy can alter the absorption, distribution, and clearance of many drugs. When presented with a clinical situation in which it does not appear that a prescribed drug is working, clinicians must either change drugs or increase the dose of the current drug to achieve the desired clinical effect. A case highlighting antihypertensive medication in pregnancy and the effect of changed drug-metabolizing enzymes is presented. Understanding pregnancy's effect on drug-metabolizing enzymes, transporters, and receptors can help clinicians make individualized pharmacotherapeutic decisions for patients. Pharmacogenetics potentially can aid clinicians in treating pregnant women in the future as more data are generated and individualized therapeutic models are constructed.