Capecitabine and Breastfeeding

Summary of use during lactation

Most sources consider breastfeeding to be contraindicated during maternal antineoplastic drug therapy.[1] It might be possible to breastfeed safely during intermittent therapy with an appropriate period of breastfeeding abstinence. some have suggested a period of 24 hours before resuming nursing,[2] although the manufacturer recommends an abstinence period of 2 weeks. Capecitabine is metabolized to fluorouracil. Limited information indicates that a maternal continuous intravenous fluorouracil infusion at a dose of 200 mg/square meter daily produces undetectable levels in milk. If capecitabine use is undertaken, monitoring of the infant's complete blood count and differential is advisable. Chemotherapy may adversely affect the normal microbiome and chemical makeup of breastmilk.[3] Women who receive chemotherapy during pregnancy are more likely to have difficulty nursing their infant.[4]

Drug levels in milk and infant serum

Capecitabine is a prodrug that is metabolized to fluorouracil. Maternal Levels. A mother who was 9 months postpartum was diagnosed with rectal cancer and began treatment with pelvic radiotherapy and a continuous intravenous infusion of fluorouracil 200 mg/square meter daily. Her plasma fluorouracil concentration was constant at about 110 micromoles/L (14.3 mg/L) from weeks 2 to 5 of therapy. She discontinued nursing her infant and pumped her breasts twice daily and collected 36 breastmilk samples before, during and for 10 days following fluorouracil therapy (exact times not specified). Fluorouracil was undetectable (<0.5 micromole/L [<65 mcg/L]) in all of the milk samples.[5] Infant Levels. Relevant published information was not found as of the revision date.

Effects in breastfed infants

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

Effects on lactation and breastmilk

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

References

1. PistilliB BellettiniG GiovannettiE Chemotherapy, targeted agents, antiemetics and growth-factors in human milk: How should we counsel cancer patients about breastfeeding? Cancer Treat Rev 2013 39 207 11 23199900 PubMed
2. JohnsonHM MitchellKB ABM clinical protocol #34: Breast cancer and breastfeeding. Breastfeed Med 2020 15 429 34 32516007 PubMed
3. UrbaniakC McMillanA AngeliniM Effect of chemotherapy on the microbiota and metabolome of human milk, a case report. Microbiome 2014 2 24 25061513 PubMed
4. StopenskiS AslamA ZhangX After chemotherapy treatment for maternal cancer during pregnancy, is breastfeeding possible? Breastfeed Med 2017 12 91 7 28170295 PubMed
5. PeccatoriFA GiovannettiE PistilliB "The only thing I know is that I know nothing": 5-fluorouracil in human milk. Ann Oncol 2012 23 543 4 22275286 PubMed