Limited information indicates that maternal doses of probenecid up to 2 grams daily produce low levels in milk and would not be expected to cause any adverse effects in breastfed infants, especially if the infant is older than 2 months. In animal studies, probenecid increased the breastmilk excretion of cimetidine, possible via an interaction with an active transport mechanism in the breast.[1] The implications of enhanced excretion of drugs given with probenecid for nursing mothers and their infants has not been studied; however, only a few drugs are known to undergo active transport into breastmilk.