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.

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.

First-generation cephalosporins have a broad antibacterial spectrum and are highly active against gram-positive bacteria. They are sensitive to penicillinase-producing and non-penicillinase-producing Staphylococcus aureus, coagulase-negative Staphylococci, Streptococcus pyogenes, Streptococcus pneumoniae, group B hemolytic Streptococci, viridans streptococci, Staphylococcus epidermidis, Corynebacterium diphtheriae, and Bacillus anthracis; highly sensitive to Haemophilus influenzae, Neisseria meningitidis, Moraxella catarrhalis, and Neisseria gonorrhoeae; moderately sensitive to some strains of Escherichia coli, Klebsiella, Salmonella, Shigella, and Proteus; sensitive to gram-positive anaerobic bacteria, and resistant to Bacteroides fragilis. They mainly inhibit the synthesis of bacterial cell walls.

This product is a first-generation cephalosporin with a broad antibacterial spectrum and strong activity against Gram-positive bacteria. Penicillinase-producing and non-penicillinase-producing Staphylococcus aureus, coagulase-negative Staphylococcus, Streptococcus pyogenes, Streptococcus pneumoniae, Group B hemolytic Streptococcus, Streptococcus viridans, Staphylococcus epidermidis, Corynebacterium diphtheriae, and Bacillus anthracis are all quite sensitive to this product. Enterococci, methicillin-resistant Staphylococcus, Listeria, and Nocardia are resistant. Haemophilus influenzae, Neisseria meningitidis, Moraxella catarrhalis, and Neisseria gonorrhoeae are highly sensitive to this product. Some strains of Escherichia coli, Klebsiella, Salmonella, Shigella, and Proteus are moderately sensitive to this product, while most of the other Gram-negative rods are resistant. Gram-positive anaerobic bacteria are sensitive to this product, and Bacteroides fragilis is resistant to this product. This product mainly inhibits the synthesis of bacterial cell walls.