It kills bacteria by inhibiting bacterial cell wall synthesis and has high resistance to β-lactamase produced by bacteria. Some common Gram-positive, Gram-negative aerobic and anaerobic pathogens are highly sensitive to this product. It is resistant to Pseudomonas aeruginosa, most strains of enterococci, and Escherichia coli.

It kills bacteria by inhibiting bacterial cell wall synthesis and has high resistance to β-lactamase produced by bacteria. Some common Gram-positive, Gram-negative aerobic and anaerobic pathogens are highly sensitive to this product. It is resistant to Pseudomonas aeruginosa, most strains of enterococci, and Escherichia coli.

Tetracycline antibiotics. This product is a broad-spectrum antibacterial agent with bactericidal effects at high concentrations. Rickettsia, Mycoplasma, Chlamydia, atypical mycobacteria, and spirochetes are also sensitive to this product. This product is more effective against Gram-positive bacteria than Gram-negative bacteria, but Enterococcus is resistant to it. Others such as Actinomycetes, Bacillus anthracis, Listeria monocytogenes, Clostridium, Nocardia, Vibrio, Brucella, Campylobacter, and Yersinia are sensitive to this product. This product has certain antibacterial activity against Neisseria gonorrhoeae, but penicillin-resistant Neisseria gonorrhoeae is also resistant to doxycycline. Due to the widespread use of tetracyclines over the years, common clinical pathogens have become seriously resistant to this product, including Gram-positive bacteria such as Staphylococcus and most Gram-negative bacilli.

Cefazolin is a first-generation cephalosporin with a broad antibacterial spectrum. Except for Enterococcus and methicillin-resistant Staphylococcus, this product has good antibacterial activity against other Gram-positive cocci, and Streptococcus pneumoniae and hemolytic Streptococcus are highly sensitive to this product. Diphtheria Corynebacterium, anthrax Bacillus, Listeria and Clostridium are also very sensitive to this product. This product has good antibacterial activity against some Escherichia coli, Proteus mirabilis and Klebsiella pneumoniae, but has poor antibacterial effect on Staphylococcus aureus. Salmonella typhi, Shigella and Neisseria are sensitive to this product, while other Enterobacteriaceae, Acinetobacter and Pseudomonas aeruginosa are resistant. Enzyme-producing Neisseria gonorrhoeae is resistant to this product; Haemophilus influenzae is only moderately sensitive. Gram-positive anaerobes and some Gram-negative anaerobes are mostly sensitive to this product. Bacteroides fragilis is resistant.

This product is a first-generation cephalosporin, which has good antibacterial effect on some strains of Gram-positive cocci such as non-penicillinase-producing and penicillinase-producing Staphylococcus aureus, coagulase-negative Staphylococci, group A hemolytic streptococci, Streptococcus pneumoniae and viridans streptococci. Anaerobic Gram-positive bacteria are mostly sensitive to this product, while Bacteroides fragilis is resistant to it. Methicillin-resistant Staphylococci and Enterococci are resistant to this product. The effect of this product on Gram-positive and Gram-negative bacteria is similar to that of cephalexin. This product has a certain effect on gonococci and is also active against enzyme-producing gonococci; its activity against Haemophilus influenzae is poor.