how medication enters breast milk
Drugs do not enter the breast milk directly from the motherâs blood. It enters the milk indirectly through the mothersâ breast tissue. During the first two weeks postpartum, medications may reach their highest concentration in the milk.
Almost without exception, as the level of the medication in the mother's plasma begins its rise, the concentration in milk begins its rise as well. Drugs both enter milk, and in most cases, exit milk as a function of the mother's plasma level.