Arsenic: In a population of women living in an area of the Argentinean Andes where drinking water contains about 200 mcg/L arsenic, the average breast milk arsenic concentration was 2.3 mcg/kg fresh weight (range 0.83 to 7.6 mcg/kg). Urinary arsenic concentrations in 2 nursing infants were low (17 and 47 mcg/L), indicating that inorganic arsenic is not secreted to any significant extent in breast milk, as matrnal blood and urine arsenic levels were 10 and 320 mcg/L respectively(Concha et.al., 1998) Concha G, Vogler G. Nermell B et.al. Internat. Arch Occup Environ Health 1998; 71:42-46 Lexapro: Lexapro(escitalopram) is just the active isomer of Celexa. The breastfeeding data in MMM on Celexa should be identical for Lexapro. We've had several reports of somnolence in breastfed babies, particularly young infants. Please watch for sedation