Serum levels of valproate and carbamazepine in breastfeeding mother-infant pairs.

Few data are available about the use of anti-convulsants during breastfeeding. In this article, three women with bipolar disorder who insisted upon breastfeeding their infants were studied. One mother was treated with carbamazepine (CBZ) and two were treated with valproate (VLP) monotherapy. Mother and infant serum levels were assessed when maternal steady-state was reached. The infant whose mother took CBZ developed a serum level that was 15% of the total maternal CBZ. Free CBZ was 20% of maternal values. The two infants whose mothers took VLP developed low serum levels (1.5 and 6.0% of maternal values). In the series, the serum levels of both CBZ and VLP were lower than previously reported values. However, information is limited and careful monitoring is recommended.