Ranitidine reaches in the milk a concentration lower than the therapeutic doses used in neonates, so it is unlikely that the drug causes adverse effects on the child. It is estimated that an infant whose mother receives 150 mg ranitidine per day, can take up to 300 mcg of substance per kilo of weight per day, equivalent to 20% of the IV dose that is used for the prevention of stress ulcer in the infant.
Drugs belonging to Anti-H 2 sub> group can produce increase of prolactin, although there are not observations about the possible influence on breastfeeding during treatment with ranitidine.
Warning of the manufacturer:
Ranitidine is excreted in breast milk. It is recommended to avoid use during pregnancy (especially in the first three months) or lactation, unless that at the physician's judgment, it were considered necessary.