1. Home>
2. Specialties>
3. Psychiatry>
4. Summary and Comment

Nursing Infants and Paroxetine Exposure

To what extent are breastfed infants exposed to medication when their mothers take SSRIs? These researchers studied paroxetine levels in 16 nursing mothers receiving paroxetine (mean dose, 23.1 mg once daily) and their infants (mean age, 21.5 weeks; mean weight, 6.6 kg).

Serum samples were collected from the mothers 2 to 5 hours post-dose and from the infants 1 to 5 hours after nursing. Levels of paroxetine in infant serum were undetectable with an assay using a 2 ng/ml level of detection. In addition, paroxetine levels were assayed in breast milk sampled over a 24-hour period at intervals of 4 to 6 hours, as well as at least 3 times during a single nursing session (to determine gradient effects). Paroxetine levels in maternal serum correlated significantly with those in breast milk. Milk collected at the end of a nursing session had higher concentrations of paroxetine. Paroxetine concentrations in breast milk did not correlate significantly with the time since the mother's last dose. Pediatricians noticed no symptoms attributable to paroxetine in the infants' sleep, activity, or elimination patterns, or in their disposition.

Comment: Similar to other recent findings (see JW Psychiatry Apr 1998, p. 31, and Br J Psychiatry 1998; 172:175), these low levels of selective serotonin reuptake inhibitors in infant serum and the lack of infant adverse effects are encouraging news. As the authors note, the acute and chronic neuronal effects of SSRIs remain unknown in human infants. However, animal studies that indicate long-lasting cerebral effects of prenatal SSRI administration (JW Psychiatry Aug 1999, p. 64, and J Child Adolesc Psychopharmacol 1999; 9:13) support the need for caution in prescribing SSRIs to nursing mothers.

— B Geller

Published in Journal Watch Psychiatry March 1, 2000

Citation(s):

Stowe ZN et al. Paroxetine in human breast milk and nursing infants. Am J Psychiatry 2000 Feb 157 185-189.

• Original article (Subscription may be required)
• Medline abstract (Free)