Can you take oseltamivir while breastfeeding?

What LactMed would consider instead

LactMed ends this record by naming the drugs it would consider in place of oseltamivir. Whether any of them fits depends on what you are treating — this is the database’s list, not a recommendation from us.

• Zanamivir

How much oseltamivir gets into breastmilk

Maternal Levels. A nursing mother who was 9 months postpartum was given oseltamivir 75 mg by mouth twice daily for 5 days. She collected 8 milk samples within 30 minutes of taking an oseltamivir dose and 2 after the last dose. Milk was analyzed for oseltamivir and its carboxylate metabolite. Oseltamivir milk concentrations fluctuated depending on the time of the milk sample, but oseltamivir carboxylate concentrations were generally higher and reached a steady-state between 37 to 39 mcg/L after 3 days of therapy. The authors calculated that at worst, the infant would receive 0.012 mg/kg daily, compared to the dosage for infants over 2 weeks of age of 3 mg/kg daily. The dose in milk corresponded to 0.5% of the mother's weight-adjusted dosage.

Seven postpartum women who were bottle feeding their infants donated milk samples at the time of and 0.5, 1, 2, 4, 8, 12, and 24 hours after a single 75 mg oral dose of oseltamivir. Both oseltamivir and its metabolite, oseltamivir carboxylate were measured in milk samples. The average peak milk level of oseltamivir of 26.9 mcg/L occurred at an average of 3.4 hours after the dose and the average peak milk level of oseltamivir carboxylate of 41.9 mcg/L occurred at an average of 18.9 hours after the dose. Using area under the curve (AUC) data reported in the paper and the standardized milk intake of 150 mL/kg daily, a fully breastfed infant would receive daily dosages of about 0.9 mcg/kg of oseltamivir and 3.6 mcg/kg of oseltamivir carboxylate. These values would be doubled with the usual dosage of 75 mg twice daily, but the sum of these entities is far below the dose reportedly used in infants of 3 mg/kg daily.

Six women with influenza were receiving oseltamivir 75 mg twice daily for 5 days. Oseltamivir and its active metabolite oseltamivir carboxylate were measured in breastmilk at 0, 1, 2, 4, 6, 8, 10, and 12 hours after the seventh dose of the drug. The peak oseltamivir concentration was found at 1.3 hours after the dose and was 69.5 mcg/L. Its half-life in milk was 2.1 hours. The peak oseltamivir carboxylate concentration was found at 5.3 hours after the dose and was 38.4 mcg/L. Its half-life in milk was 12.5 hours. Although the study was not powered to measure colostrum and breastmilk separately, the study found no significant difference in the pharmacokinetics between colostrum collected within 5 days of birth in 3 women and breastmilk from 3 women who were 13 days postpartum.

Infant Levels. Relevant published information was not found as of the revision date.

What has been seen in breastfed infants

Relevant published information was not found as of the revision date.

Effects on milk supply

Relevant published information was not found as of the revision date.