Background: During treatment of postpartum depression with antidepressant drugs, the mothers often strongly wish to continue breast-feeding although the long-term safety of exposing infants to low doses of antidepressants has not been established.
Methods: Citalopram in breast milk and in the serum of a nursing mother and her infant was determined by high-performance liquid chromatography.
Results: During treatment with 40 mg/day of citalopram, the concentration of the drug in milk and serum was 205 ng/mL and 98.9 ng/mL, respectively. Her infant obtained 12.7 ng/mL of citalopram in serum and uneasy sleep was observed. Sleep was normalized when the dose was halved and two breast-feedings were replaced with artificial nutrition.
Conclusion: The amount of citalopram and other selective serotonin inhibitors (SSRIs) passed to breast milk and delivered to the child correlates to the serum concentration of the mother. The lowest possible effective serum concentration should be used and breast-feeding during the drug absorption phase may be avoided.