CASRN: 25953-19-9
Drug Levels and Effects
Summary of Use during Lactation
Limited information indicates cefazolin produces low levels in milk that are not expected to cause adverse effects in breastfed infants. Occasionally disruption of the infant's gastrointestinal flora, resulting in diarrhea or thrush have been reported with cephalosporins, but these effects have not been adequately evaluated. Cefazolin is acceptable in nursing mothers.
Drug Levels
Maternal Levels. After a single 500 mg dose of cefazolin intramuscularly to 4 women, cefazolin was barely detectable in the mother's milk and not detected in their breastfed infants' serum.[1]
After intramuscular doses of cefazolin 500 mg three times daily in 10 women, the peak concentration of cefazolin in milk was 0.9 mg/L.[2]
Twenty women were given 2 grams of cefazolin intravenously over 10 minutes. Average milk levels were 1.25 mg/L at 2 hours, 1.51 mg/L at 3 hours and 1.16 mg/L at 4 hours after the dose.[3]
After a single dose of 1 gram of cefazolin given intravenously to 15 women who were 1 month postpartum, milk cefazolin levels averaged 0.75 mg/L 2 hours after the dose.[4]
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.
Alternate Drugs to Consider
(Methicillin-sensitive Staph. aureus) Cephalexin, Dicloxacillin, Floxacillin, Oxacillin, Methicillin, Nafcillin; (Methicillin-resistant Staph. aureus) Doxycycline, Linezolid, Minocycline, Trimethoprim-Sulfamethoxazole, Vancomycin
References
- 1.
- Fukada M. Studies on chemotherapy during the perinatal period with special reference to such derivatives of cephalosporin C as cefazolin, cephaloridine and cephalothin. Jpn J Antibiot 1973;26:197-214. [PubMed: 4542543]
- 2.
- von Kobyletzki D, Reither K, Gellen J, et al. Pharmakokinetische untersuchungen mit cefazolin in geburtshilfe und gynakologie. Infection 1974;2 (Suppl 1):60-7.
- 3.
- Yoshioka H, Cho K, Takimoto M, et al. Transfer of cefazolin into human milk. J Pediatr 1979;94:151-2. [PubMed: 758399]
- 4.
- Zhang Y, Zhang Q, Xu Z. Tissue and body fluid distribution of antibacterial agents in pregnant and lactating women. Zhonghua Fu Chan Ke Za Zhi 1997;32:288-92. [PubMed: 9596854]
Substance Identification
Substance Name
Cefazolin
CAS Registry Number
25953-19-9
Drug Class
Breast Feeding
Lactation
Milk, Human
Anti-Infective Agents
Antibacterial Agents
Cephalosporins
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.
Publication Details
Publication History
Last Revision: November 15, 2024.
Copyright
Attribution Statement: LactMed is a registered trademark of the U.S. Department of Health and Human Services.
Publisher
National Institute of Child Health and Human Development, Bethesda (MD)
NLM Citation
Drugs and Lactation Database (LactMed®) [Internet]. Bethesda (MD): National Institute of Child Health and Human Development; 2006-. Cefazolin. [Updated 2024 Nov 15].