Background: Few reports exist on the levels of antidepressants in breast milk or on observed behavioral effects, if any, of neonates who are breast-fed. Thus, a dilemma exists for women who would like to breast-feed but require psychotropic medications.
Method: Analysis of sertraline levels was performed on eight samples of breast milk obtained over a 24-hour period, after 3 weeks of breastfeeding, from a lactating patient taking sertraline and nortriptyline. During this same 24-hour period, two serum samples each were taken from mother and child for analysis of sertraline and nortriptyline levels. After 7 weeks of exclusive breastfeeding, an additional serum sample was obtained from mother and child for analysis of sertraline levels. Drug metabolites were not measured.
Results: Breast milk levels of sertraline were lowest 1 hour before the ingestion of sertraline and highest 5 to 9 hours after ingestion of the drug. The infant's serum sertraline and nortriptyline levels were nondetectable.
Conclusion: These data indicate that sertraline levels in breast milk vary substantially over 24 hours and appear to be lowest within the 2 hours before and 1 hour after ingestion of the medication, with the peak probably occurring between Hours 1 and 9 postingestion. However, the absence of detectable serum sertraline and nortriptyline levels in the infant suggests that if either medication is present in infant serum, its concentration would be extremely low. No abnormal occurrences have been noted in the development of the infant. It would be important in future studies to measure metabolites in addition to medication levels since the former have been associated with untoward events in an infant.