Balsalazide and Breastfeeding

Summary of use during lactation

Although no information exists on the excretion of balsalazide into breastmilk, it is metabolized to the active drug mesalamine. A few cases of diarrhea have been reported in infants exposed to mesalamine, although the rate is not high. Most experts and professional guidelines consider mesalamine derivatives to be acceptable during breastfeeding.[1-7] If balsalazide is required by the mother, it is not a reason to discontinue breastfeeding, but observe breastfed infants for diarrhea.

Drug levels in milk and infant serum

Balsalazide is a prodrug that liberates the active drug, mesalamine (5-aminosalicylic acid; 5-ASA), in the gastrointestinal tract. Mesalamine is metabolized to N-acetyl-5-ASA, which is inactive in treating inflammatory bowel disease, but its possible effects on the breastfed infant are unknown. Maternal Levels. Relevant published information was not found as of the revision date. Infant Levels. Relevant published information was not found as of the revision date.

Effects in breastfed infants

The active metabolite of balsalazide, mesalamine, was probably responsible for diarrhea in a 6-week-old whose diarrhea recurred 4 times after rechallenging of the mother 4 times during breastfeeding.[8] In a prospective telephone follow-up study, 8 nursing mothers reported taking mesalamine (dosage and route unspecified). One mother reported diarrhea in her infant. No other adverse reactions were reported in the infants by their mothers.[9] A case-control study compared the infants of mothers taking mesalamine (n = 117; average dose, 2065 mg daily), olsalazine (n = 2) or sulfasalazine (n = 2) to infants of matched control mothers (n = 121) who were exposed to no treatment known to be harmful to a breastfed infant. Infants were exposed to mesalamine through milk for a mean of 5.3 months (range: 3 days-24 months). Infants were breastfed for an average of about 7.4 months and were followed up at an average age of about 22 months. No difference in the frequency or characteristics of maternally reported adverse events were found between exposed and control infants.[10,11]

Effects on lactation and breastmilk

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

Alternative drugs to consider

(Inflammatory Bowel Disease) Adalimumab, Azathioprine, Budesonide, Certolizumab Pegol, Infliximab, Mesalamine, Prednisone, Sulfasalazine

References

1. Mahadevan U, Robinson C, Bernasko N, et al. Inflammatory bowel disease in pregnancy clinical care pathway: A report from the American Gastroenterological Association IBD Parenthood Project Working Group. Gastroenterology 2019;156:1508–24.30658060 PubMed
2. Sammaritano LR, Bermas BL, Chakravarty EE, et al. 2020 American College of Rheumatology Guideline for the Management of Reproductive Health in Rheumatic and Musculoskeletal Diseases. Arthritis Rheumatol 2020;72:529–56.32090480 PubMed
3. Yeung J, Gooderham MJ, Grewal P, et al. Management of plaque psoriasis with biologic therapies in women of child-bearing potential consensus paper. J Cutan Med Surg 2020;24 (1_Suppl):3S–14S.32500730 PubMed
4. Russell MD, Dey M, Flint J, et al. British Society for Rheumatology guideline on prescribing drugs in pregnancy and breastfeeding: Immunomodulatory anti-rheumatic drugs and corticosteroids. Rheumatology (Oxford) 2023;62:e48–e88.36318966 PubMed
5. Torres J, Chaparro M, Julsgaard M, et al. European Crohn's and Colitis Guidelines on Sexuality, Fertility, Pregnancy, and Lactation. J Crohns Colitis 2023;17:1–27.36005814 PubMed
6. Rüegg L, Pluma A, Hamroun S, et al. EULAR recommendations for use of antirheumatic drugs in reproduction, pregnancy, and lactation: 2024 update. Ann Rheum Dis 2025;84:910–26.40287311 PubMed
7. Mahadevan U, Seow CH, Barnes EL, et al. Global consensus statement on the management of pregnancy in inflammatory bowel disease. Clin Gastroenterol Hepatol 2025;23 (11S):S1–S60.40874901 PubMed
8. Nelis GF. Diarrhoea due to 5-aminosalicylic acid in breast milk. Lancet 1989;333:383.2563532 PubMed
9. 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;168:1393–9.8498418 PubMed
10. Moretti ME, Spiczynski Y, Hashemi G, et al. Prospective follow-up of infants exposed to 5-aminosalicylic acid containing drugs through maternal milk. J Clin Pharmacol 1998;38:867. doi:10.1177/009127009803800901 PubMed
11. Moretti ME. Prospective follow-up of infants exposed to 5-aminosalicylic acid containing drugs through maternal milk. Theses Canada 1998 https://library-archives.canada.ca/eng/services/services-libraries/theses/Pages/item.aspx?idNumber=51446896 PubMed