Is Naproxen safe while breastfeeding?

Here is what LactMed, the Drugs and Lactation Database published by the U.S. National Institute of Child Health and Human Development (NICHD), reports about Naproxen. The text below is quoted from that source — it is not our own verdict.

Summary of use during breastfeeding

Limited information indicates that levels of naproxen in breastmilk are low and adverse effects in breastfed infants are apparently uncommon. However, because of naproxen’s long half-life and reported serious adverse reaction in a breastfed neonate, other agents may be preferred while nursing a newborn or preterm infant.

Effects on the breastfed infant

Naproxen possibly caused prolonged bleeding time, thrombocytopenia and acute anemia in one 7-day-old infant of a mother also taking bacampicillin.[3]

In one telephone follow-up study of 20 infants (ages not stated) exposed to naproxen during breastfeeding, 2 mothers reported drowsiness and 1 reported vomiting in their infants. None of the reactions required medical attention.[4]

Effects on milk supply

A randomized study compared naproxen and tramadol for post-cesarean section pain. Patients received the drugs either on a fixed schedule or as needed. No difference in breastfeeding rates were seen among the groups.[5]

Levels in milk

Maternal Levels. Peak milk naproxen levels in a 5-month postpartum patient were 1.1 to 1.3 mg/L while taking oral naproxen 250 mg twice daily and 2.4 mg/L with a dose of 375 mg twice daily. Peak milk levels occurred 4 to 5 hours after the dose and fell slowly over 12 to 24 hours. From urinary excretion data the authors estimated that the infant received 0.26% of the mother’s total dose or 1.9% of the maternal weight-adjusted dosage.[1,2] Using the peak milk level data, the estimated maximum intake of an exclusively breastfed infant would be 2.2 to 2.8% of the maternal weight-adjusted dosage, not including the contribution of any glucuronide metabolite.

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

Alternatives LactMed lists

Naproxen in pregnancy

LactMed covers breastfeeding only. For what the NHS and the US prescribing label say about pregnancy, see:

Source: Drugs and Lactation Database (LactMed), National Institute of Child Health and Human Development (NICHD), via NCBI Bookshelf, record “Naproxen” (LM195). LactMed on NCBI Bookshelf. LactMed is a registered trademark of the U.S. Department of Health and Human Services.

Educational summary of an authoritative source — not medical advice. Never start, stop, or change a medicine while breastfeeding without confirming with your doctor.