Paulina Opalska, Magdalena Elżbieta Hurkacz

Safety of drugs used during pregnancy and lactation as a result of changes in their pharmacokinetics
2022-12-29

Over-the-counter medications, and dietary supplements are commonly available, relatively inexpensive and perceived as safe. However, special attention should be paid to the intake of such preparations by vulnerable populations, which include pregnant women and nursing mothers. The body of a pregnant woman undergoes many adaptive changes of a physiological and anatomical nature. The pharmacokinetics of ingested substances changes, which has an effect on the occurrence of a therapeutic or toxic effect after the use of a drug or supplement. Different drug absorption, distribution, metabolism, and excretion require special caution and an individualized approach by healthcare professionals toward pregnant women. The human placenta was formerly considered a natural barrier, protecting the fetus from xenobiotics ingested by the mother. Today, it is known that many substances can penetrate the placental barrier by various mechanisms, including passive diffusion and active transport. The human placenta also has the metabolic activity to carry out the biotransformation of compounds of endogenous and exogenous origin. Drugs and supplements taken by women penetrate not only through the placenta but also breast milk and thus can exert their effects on the fetus and child. The physiological dissimilarity of such a young organism and underdeveloped metabolic systems may cause a modified response of the child’s body to the applied product. There are many classification systems for drugs and dietary supplements used during pregnancy or breastfeeding. In 2015, the FDA began implementing a new labeling and classification system for drugs used during pregnancy and lactation called the Pregnancy and Lactation Labeling (Drugs) Rule (PLLR). It was intended to replace the previously used classification of five letter risk categories (A, B, C, D, X) which was considered to be misinterpreted. Meanwhile, Prof. Hale’s classification became the standard reference for the use of drugs during breastfeeding.

Keywords: lactation, dietary supplements, OTC drugs, Pregnancy.

© Farm Pol, 2022, 78(10): 589–596