Also known as (+)-Naproxen, (S)-Naproxen, Naprolag, Naprosyn, Naproxeno, Naproxenum, Naproxène, RS-3540

A propionic acid derivative and a non-steroidal anti-inflammatory drug (NSAID) with anti-inflammatory, antipyretic and analgesic activities. Naproxen inhibits the activity of the enzymes cyclo-oxygenase I and II, resulting in a decreased formation of precursors of prostaglandins and thromboxanes. The resulting decrease in prostaglandin synthesis is responsible for the therapeutic effects of naproxen. Naproxen also causes a decrease in the formation of thromboxane A2 synthesis, by thromboxane synthase, thereby inhibiting platelet aggregation.

Originator: NCI Thesaurus | Source: The website of the National Cancer Institute (http://www.cancer.gov)

Can I take Naproxen while 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.

Drug levels

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] 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.

Effects in breastfed infants

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] 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.

Possible effects on lactation

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]

Alternate drugs to consider

Acetaminophen, Flurbiprofen, Ibuprofen, Indomethacin, Piroxicam

References

1. Jamali F, Tam YK, Stevens RD. Naproxen excretion in breast milk and its uptake by suckling infant. Drug Intell Clin Pharm. 1982;16:475. Abstract. PMID: 6653409

2. Jamali F, Stevens DR. Naproxen excretion in milk and its uptake by the infant. Drug Intell Clin Pharm. 1983;17:910-1. Letter. PMID: 6653409

3. Fidalgo I, Correa R, Gomez Carrasco JA et al. [Acute anemia, rectorrhagia and hematuria caused by ingestion of naproxen]. An Esp Pediatr. 1989;30:317-9. PMID: 2787136

4. Ito S, Blajchman A, Stephenson M et al. Prospective follow-up of adverse reactions in breast-fed infants exposed to maternal medication. Am J Obstet Gynecol. 1993;168:1393-9. PMID: 8498418

5. Sammour RN, Ohel G, Cohen M, Gonen R. Oral naproxen versus oral tramadol for analgesia after cesarean delivery. Int J Gynaecol Obstet. 2011;113:144-7. PMID: 21435642

Last Revision Date

20150310

Disclaimer:Information presented in this database is not meant as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. The U.S. government does not warrant or assume any liability or responsibility for the accuracy or completeness of the information on this Site.

Source: LactMed – National Library of Medicine (NLM)

3D Model of the Naproxen molecule

MolView – data visualization platform