Sulfisoxazole use while Breastfeeding
Drugs containing Sulfisoxazole: Gantrisin, Pediazole, Eryzole, Truxazole, Gantrisin Ophthalmic, Gantrisin Pediatric, Azo-Truxazole, Sulfimycin, E S P, Azo Gantrisin
Sulfisoxazole Levels and Effects while Breastfeeding
Summary of Use during Lactation
With healthy, full-term infants it appears acceptable to use sulfisoxazole during breastfeeding after the newborn period.[1][2] Until further data are accumulated, alternate agents should probably be used in jaundiced, ill, stressed or premature infants, because of the risk of bilirubin displacement and kernicterus. Sulfisoxazole should be avoided while breastfeeding a G6PD-deficient infant.
Drug Levels
Maternal Levels. Following oral sulfisoxazole doses of 1 g every 6 hours for 4 doses to 6 women (time postpartum not stated), an average total recovery of sulfisoxazole and N4-acetylsulfisoxazole of 18 mg was obtained during the 48 hours from the time of the first dose. About 77% of the drug in milk was recovered as the metabolite. This averaged 0.45% of the maternal dose (not weight-adjusted).[3] This study may have underestimated the amount excreted by a small fraction, because steady-state metabolite serum levels were not achieved during the study period.[1][4]
Infant Levels. A 9-month-old infant was breastfed twice daily during maternal treatment for a urinary tract infection (dosage not stated). Urine was collected during a 24-hour time period from the infant. The infant excreted 1.1 mg of sulfisoxazole plus N4-acetylsulfisoxazole over the time period.[3]
Effects in Breastfed Infants
Relevant published information was not found as of the revision date.
Possible Effects on Lactation
Relevant published information was not found as of the revision date.
Alternate Drugs to Consider
Sulfamethoxazole, Trimethoprim-Sulfamethoxazole
References
1. Kauffman RE. Sulfisoxazole in human milk. Reply. J Pediatr. 1981;99:172-3.
2. Chung AM, Reed MD, Blumer JL. Antibiotics and breast-feeding: a critical review of the literature. Paediatr Drugs. 2002;4:817-37. PMID: 12431134
3. Kauffman RE, O'Brien C, Gilford P. Sulfisoxazole secretion into human milk. J Pediatr. 1980;97:839-41. PMID: 7431180
4. Elliott GT, Quinn SL. Sulfisoxazole in human milk. J Pediatr. 1981;99:171-3. Letter. PMID: 7252664
Sulfisoxazole Identification
Substance Name
CAS Registry Number
127-69-5
Drug Class
- Antiinfective Agents
- Antibacterial Agents
- Sulfonamides
Administrative Information
LactMed Record Number
416
Information from the National Library of Medicine's LactMed Database.
Last Revision Date
2012-05-03
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.
See Also...
- Sulfisoxazole use during Pregnancy
- Sulfisoxazole ophthalmic Consumer Information
- Sulfisoxazole Consumer Information
- Breastfeeding Support Group
- Safe Medications during Breastfeeding
- Medicine use while Breastfeeding
- Medicine use during Pregnancy
Disclaimer: This information is not intended as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. Use of this website signifies your agreement to the Terms of Use and Online Privacy Policy.


