Maternal cimetidine doses of 1000 to 1200 mg daily result in infant dosages that are much less than reported neonatal dosages of 5 to 10 mg/kg daily. Cimetidine would not be expected to cause any adverse effects in breastfed infants, especially if the infant is older than 2 months. However, because of its potential for causing hepatic enzyme inhibition, other drugs might be preferred. Cimetidine can increase serum prolactin and it has been used, but not validated, as a galactogogue.