When discussing the use of antidepressant medications by breastfeeding women, It is somewhat misleading to say that certain medications are “safer” than others. All medications taken by the mother are secreted into the breast milk. The amount of drug to which the infant is exposed depends on many factors, including the medication dosage, as well as the infant’s age and feeding schedule. To date, we have not found that certain medications are found at lower levels in the breast milk and may therefore pose less of a risk to the nursing infant. Nor have we found that any antidepressant medication has been associated with serious adverse events in the baby.
In general, one should try to choose an antidepressant for which there are data to support its safety during breastfeeding. The most information is available on fluoxetine (Prozac), followed by sertraline (Zoloft), paroxetine (Paxil), and the tricyclic antidepressants. Other antidepressant medications have not been studied as well.
We do not regularly measure drug levels in the breastfeeding mother or baby; however, there may be certain situations where information on exposure to drug in the child may help make decisions regarding treatment. If there is a significant change in the child’s behavior (e.g., irritability, sedation, feeding problems, or sleep disturbance) an infant serum drug level may be obtained. If levels are high, breastfeeding may be suspended. Similarly if the mother is taking a particularly high dosage of medication, it may be helpful to measure drug levels in the infant to determine the degree of exposure.
Burt VK, Suri R, Altshuler L, Stowe Z, Hendrick VC, Muntean E. The use of psychotropic medications during breast-feeding. Am J Psychiatry 2001; 158: 1001-9.