Serum fluvoxamine levels in breastfed infants

Background: Between 10% and 15% of new mothers will experience an episode of postpartum depression. Although antidepressants are effective agents for the treatment of postpartum depression, minimal data are available to support their safety in infants of breastfeeding mothers. Method: In this article, we present 2 cases of nursing mother-infant pairs in which the mother was treated with fluvoxamine and in which infant serum fluvoxamine levels were obtained. Both mothers began the fluvoxamine treatment postpartum, and serum levels were obtained from mothers and infants after a minimum of 7 days on a stable maternal dose. One level was obtained from the infant in case 1, and 2 levels were obtained from the infant in case 2. Results: Each of the infant serum fluvoxamine levels obtained was too low to quantify (at a limit of detection of 2.5 ng/mL). Neither of the infants experienced adverse events related to the mother's treatment with fluvoxamine. Each of the infants is reportedly healthy 2 to 3 years after the exposure. Conclusion: While these results are encouraging, they are limited and cannot be generalized to all cases of infants exposed to fluvoxamine. Additional mother-infant serum fluvoxamine levels and infant behavioral observations will facilitate the risk-benefit decision-making process for women who choose to breast-feed while taking fluvoxamine.