Drug Levels and Effects:

Summary of Use during Lactation:

Cefprozilis acceptable to use during breastfeeding. Limited information indicates that maternal doses of cefprozil up to 1 gram produce 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, has been reported with cephalosporins, but these effects have not been adequately evaluated.

Drug Levels:

Maternal Levels.

Nine healthy women were given a single 1 gram dose of cefprozil orally 6 to 12 months postpartum. Milk levels of cis- cefprozil (which accounts for 90% of cefprozil ) ranged from 0.7 to 1.3 mg/L during the 12 hours after the dose. The peak level averaged 3.4 mg/L at 6 hours after the dose. By 24 hours after the dose, milk cefprozil levels were 0.3 mg/L.[1][2] Using the peak milk level value and assuming that the trans-isomer adds an additional 10% to the peak, an exclusively breastfed infant would receive a maximum of 3.3% of the weight-adjusted maternal 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.

Possible Effects on Lactation:

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


1. Shyu WC, Shah VR, Venitz J et al. The excretion of cefprozil (CPR) into breast milk. Clin Pharmacol Ther. 1992;51:182. Abstract.
2. Shyu WC, Shah VR, Campbell DA et al. Excretion of cefprozil into human breast milk. Antimicrob Agents Chemother. 1992;36:938-41. PMID:1510416

Substance Identification:

Substance Name:


CAS Registry Number:


Drug Class:

  • Antiinfective Agents

  • Antibacterial Agents

  • Cephalosporins

  • Administrative Information:

    LactMed Record Number:


    Last Revision Date:

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