IBCLC Practice Exam 2026 – Complete Preparation Guide

Relative Infant Dose (RID) refers to the percentage of the maternal drug dose that is passed to the infant through breast milk. This measurement is crucial in assessing the potential exposure of breastfeeding infants to medications that their mothers may be taking. RID provides healthcare professionals with valuable information regarding the safety of breastfeeding while on medication, helping to evaluate whether the benefits of continuing to breastfeed outweigh any potential risks associated with the drug's presence in breast milk.

Understanding RID is essential for lactation consultants and healthcare providers when advising mothers about medication use during breastfeeding. By calculating the RID, clinicians can offer evidence-based recommendations that ensure both the health of the infant and the wellbeing of the mother.

While the amount of drug in the bloodstream, total dose consumed by the infant, and risk factors for infant toxicity are related concepts, they do not accurately define what RID specifically measures, which is the proportion of the maternal drug dose that the infant is exposed to via breast milk.