This product is a second-generation cephalosporin drug with a broad-spectrum antibacterial effect. Its bactericidal mechanism is to hinder the synthesis of bacterial cell walls. In vitro tests have shown that cefprozil has a significant effect on Gram-positive aerobic bacteria such as Staphylococcus aureus (including β-lactamase-producing strains), Streptococcus pneumoniae, and Streptococcus pyogenes, and has an inhibitory effect on Enterococcus tenacious, Listeria monocytogenes, Staphylococcus epidermidis, Staphylococcus saprophyticus, Staphylococcus Wamei, Streptococcus agalactiae, Streptococcus C, D, F, G groups, and Streptococcus viridans. It is ineffective against methicillin-resistant Staphylococci and Enterococcus spp. It is highly sensitive to the gram-negative aerobic bacteria Haemophilus influenzae (including β-lactamase-producing strains) and Moraxella catarrhalis (including β-lactamase-producing strains); it can inhibit the growth of Citrobacter diversus, Escherichia coli, Klebsiella pneumoniae, Neisseria gonorrhoeae (including β-lactamase-producing strains), Proteus mirabilis, Salmonella, Shigella and Vibrio, but has no antibacterial effect on most strains of Acinetobacter, Encephalobacter, Morganella morganii, Proteus vulgaris, Providencia and Pseudomonas. Cefprozil has a certain inhibitory effect on melanin Bacillus, Clostridium difficile, Clostridium perfringens, Fusobacterium, Streptococcus and Propionibacterium acnes among anaerobic bacteria, but has no antibacterial effect on most strains of Bacillus fragilis.