What is the threshold for considering a drug safe for a breastfeeding neonate?

When evaluating the safety of a medication for a breastfeeding neonate, the relative infant dose (RID) is a critical consideration. The threshold for a safe drug is typically considered to be less than 10% RID. This percentage is based on the understanding that exposure through breast milk should be sufficiently low to minimize any potential effects on the infant.

A relative infant dose of less than 10% indicates that the amount of the drug the infant is exposed to via breastfeeding is relatively small compared to the therapeutic dose given to adults. This threshold helps ensure that any potential risk of adverse effects in the neonate is greatly reduced. Therefore, when a medication has an RID of less than 10%, it is generally viewed as safe for nursing mothers to use without significant concern for the health of their breastfeeding infants.

This standard aligns with clinical guidelines that emphasize the importance of assessing drug exposure in infants while considering the benefits of breastfeeding.