Zafirlukast Levels and Effects while Breastfeeding
Summary of Use during Lactation
No published information is available on the use of zafirlukast during breastfeeding; however, manufacturer's data indicate that the dose in milk is low. Zafirlukast has been used in children as young as 12 months of age.[1] International guidelines consider that leukotriene receptor antagonists can be used during breastfeeding.[2,3]
Drug Levels
Maternal Levels. Relevant published information was not found as of the revision date.
The manufacturer reports that after administration of zafirlukast 40 mg twice daily to lactating women (number not reported), average steady-state milk concentrations were 50 mcg/L. Using these data, a fully breastfed infant would be expected to receive about 0.6% of the maternal weight-adjusted dosage.
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.
Berlin CM, Briggs GG. Drugs and chemicals in human milk. Semin Fetal Neonatal Med 2005;10:149-59 [PubMed: 15701580]
2.
Middleton PG, Gade EJ, Aguilera C, et al. ERS/TSANZ Task Force Statement on the management of reproduction and pregnancy in women with airways diseases. Eur Respir J 2020;55:1901208 [PubMed: 31699837]
3.
Bendien SA, de Kruif MD, Feitsma H, et al. Summary of the Dutch Multidisciplinary Practice Guideline on Asthma and Pregnancy. J Allergy Clin Immunol Pract 2024;12:1751-62 [PubMed: 38513758]
Substance Identification
Substance Name
Zafirlukast
CAS Registry Number
107753-78-6
Drug Class
Breast Feeding
Lactation
Milk, Human
Anti-Asthmatic Agents
Leukotriene Antagonists
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.