Is Omeprazole safe while breastfeeding?

Effects on the breastfed infant

One mother taking oral omeprazole 20 mg daily pumped and discarded her milk once each day 4 hours after her morning dose. She breastfed her infant the remainder of the day for 3 months before weaning. The infant remained well at 12 months of age.[ 1 ]

Effects on milk supply

The Spanish pharmacovigilance system found 20 cases of gynecomastia reported in patients taking omeprazole during the time period of 1982 to 2006.[ 2 ] A retrospective claims database study in the United States found that users of proton pump inhibitors had an increased risk of gynecomastia.[ 3 ] A review article reported that a search of database from the European Pharmacovigilance Centre found 104 cases of gynecomastia, 15 cases of galactorrhea, 15 cases of breast pain and 16 cases of breast enlargement associated with omeprazole. A search of the WHO global pharmacovigilance database found 439 cases of gynecomastia, 46 cases of galactorrhea, 93 cases of breast pain and 63 cases of breast enlargement associated with omeprazole.[ 4 ] A 13-year-old girl was placed on omeprazole 20 mg twice daily by mouth for dyspepsia caused by mefenamic acid and a Helicobacter pylori infection. After 2 days of therapy, she developed bilateral galactorrhea and elevated serum prolactin. Three weeks after discontinuing omeprazole, galactorrhea and hyperprolactinemia resolved. Six weeks later, she was rechallenged with omeprazole and her serum prolactin rose from 27 to 70 mcg/L. Prolactin returned to normal 2 weeks after omeprazole discontinuation. Over the next 6 months, she was given domperidone on one occasion and lansoprazole on another. With both drugs, she developed galactorrhea and hyperprolactinemia which returned to normal after drug discontinuation.[ 5 ] The prolactin level in a mother with established lactation may not affect her ability to breastfeed. A 26-year-old woman with a kidney transplant developed galactorrhea after her kidney function decreased. She was taking tacrolimus, prednisone, amlodipine, labetalol, lovastatin, nortriptyline and pyridoxine as well as omeprazole for heartburn. Her omeprazole dose had been increased from 20 mg twice a day to 40 mg twice a day 3 months prior. A week earlier, she had been given prescriptions for naratriptan for migraine and metoc

Levels in milk

Maternal Levels. A woman taking oral omeprazole 20 mg daily for gastroesophageal reflux had omeprazole measured in her milk 3 weeks postpartum. The milk omeprazole level was not detectable for 90 minutes after the dose and then reached a peak of 20 mcg/L at 3 hours after the dose.[ 1 ] Using the peak milk level in this patient, the maximum dose that an exclusively breastfed infant would receive in breastmilk would be 3 mcg/kg daily or about 0.9% of the maternal weight-adjusted dosage. For comparison, doses of 1 mg/kg daily have been used in neonates. Infant Levels. Relevant published information was not found as of the revision date.

Alternatives LactMed lists

• Antacids
• Cimetidine
• Famotidine
• Pantoprazole
• Sucralfate