Cefprozil has in vitro activity against a broad range of gram-positive and gram-negative bacteria. The bactericidal action of cefprozil results from inhibition of cell-wall synthesis. Cefprozil has been shown to be active against most strains of the following microorganisms both in vitro and in clinical infections as described in the INDICATIONS AND USAGE section.
Aerobic gram-positive microorganisms: Aerobic gram-negative microorganisms:
Staphylococcus aureus (including Haemophilus influenzae (including β-lactamase-
β-lactamase-producing strains) producing strains)
NOTE: Cefprozil is inactive against Moraxella (Branhamella) catarrhalis
methicillin-resistant staphylococci. (including β-lactamase-producing strains)
Streptococcus pneumoniae
Streptococcus pyogenes
The following in vitro data are available; however, their clinical significance is unknown. Cefprozil exhibits in vitro minimum inhibitory concentrations (MICs) of 8 mcg/mL or less against most (≥90%) strains of the following microorganisms; however, the safety and effectiveness of cefprozil in treating clinical infections due to these microorganisms have not been established in adequate and well-controlled clinical trials.
Aerobic gram-positive microorganisms:
Enterococcus durans Staphylococcus warneri
Enterococcus faecalis Streptococcus agalactiae
Listeria monocytogenes Streptococci (Groups C,D,F, and G)
Staphylococcus epidermidis viridans group Streptococci
Staphylococcus saprophyticus
NOTE: Cefprozil is inactive against Enterococcus faecium.
Aerobic gram-negative microorganisms:
Citrobacter diversus Proteus mirabilis
Escherichia coli Salmonella spp.
Klebsiella pneumoniae Shigella spp.
Neisseria gonorrhoeae Vibrio spp.
(including β-lactamase-producing strains)
NOTE: Cefprozil is inactive against most strains of Acinetobacter, Enterobacter, Morganella morganii, Proteus vulgaris, Providencia, Pseudomonas, and Serratia.
Anaerobic microorganisms:
Prevotella (Bacteroides) melaninogenicus Fusobacterium spp.
Clostridium difficile Peptostreptococcus spp.
Clostridium perfringens Propionibacterium acnes
NOTE: Most strains of the Bacteroides fragilis group are resistant to cefprozil.
Susceptibility Testing
For specific information regarding susceptibility test interpretive criteria and associated test methods and quality control standards recognized by FDA for this drug, please see: https://www.fda.gov/STIC.