International Board of Certified Lactation Consultant (IBCLC) Practice Exam

What potential effect does low oral bioavailability of a medication have on breastfeeding?

1. Higher risk of side effects for the infant

2. Lower transfer of the medication into breastmilk

3. Increased concentrations in breastmilk

4. No effect on medication transfer

The correct answer is: Lower transfer of the medication into breastmilk

Low oral bioavailability of a medication refers to the proportion of the drug that enters the systemic circulation when introduced into the body through the oral route, which is often much lower than 100%. When a medication has low oral bioavailability, it means that a smaller amount of the active drug is absorbed into the bloodstream. In the context of breastfeeding, this can lead to a lower transfer of that medication into breast milk because only a fraction of the administered dose reaches the systemic circulation and can subsequently be excreted into breast milk. This concept is important for lactation consultants, as understanding the pharmacokinetics of medications helps in assessing the safety of medication use during breastfeeding. A lower concentration of medication in breast milk decreases the potential exposure of the infant to that drug, minimizing the risk of adverse effects or toxicity associated with higher levels of medication transfer. Keeping this in mind helps health care providers make informed decisions about prescribing medications to breastfeeding mothers, ensuring both maternal health and infant safety.