Cephalexin is a first-generation cephalosporin with an antibacterial spectrum similar to that of cephalothin, but its antibacterial activity is poorer than that of the latter. Except for Enterococcus and methicillin-resistant Staphylococci, most strains of Streptococcus pneumoniae, hemolytic Streptococcus, and Staphylococcus aureus that produces or does not produce penicillinase are sensitive to this product. This product has a good antibacterial effect on Neisseria, but Haemophilus influenzae is less sensitive to this product; this product has a certain antibacterial effect on some Escherichia coli, Proteus mirabilis, Salmonella and Shigella. The remaining Enterobacteriaceae, Acinetobacter, Pseudomonas aeruginosa, and Bacteroides fragilis are resistant to this product. Fusobacterium and Veillonella are generally sensitive to this product, and anaerobic Gram-positive cocci are moderately sensitive to this product.

This product is a semi-synthetic 14-membered macrolide antibiotic. Its antibacterial spectrum and antibacterial effect are basically similar to those of erythromycin. Its effect on Gram-positive bacteria is slightly worse than that of erythromycin, but its effect on Legionella pneumophila is stronger than that of erythromycin. Its antimicrobial effect on Chlamydia pneumoniae, Mycoplasma pneumoniae, and Ureaplasma urealyticum is similar to or slightly stronger than that of erythromycin.

This product is a broad-spectrum semi-synthetic penicillin with extremely low toxicity. The antibacterial spectrum is similar to that of penicillin, and it has a strong antibacterial effect on grass-green streptococci, hemolytic streptococci, and enterococci. Diphtheria bacillus, anthrax bacillus, Gram-positive anaerobic cocci and bacilli are sensitive to this product; meningococci, pertussis bacilli, and Brucella are also very sensitive. Escherichia coli, Salmonella, Shigella dysenteriae, Proteus, influenza bacilli, pneumococci, gonococci, etc., all have varying degrees of drug resistance because some strains produce beta-lactamase. Among them, the resistance rate of Escherichia coli is as high as 50-60%. Enterobacter bacteria, Pseudomonas aeruginosa, and anaerobic Gram-negative bacilli are resistant to this product. It is mainly used to treat infectious diseases caused by sensitive Staphylococcus aureus, hemolytic streptococci, gonococci, meningococci, diphtheria, pertussis, influenza bacilli, Salmonella, Shigella, etc.; such as respiratory tract infections (pneumonia, acute and chronic bronchitis, whooping cough, etc.), gastroenteritis and digestive tract infections (liver and gallbladder infections, acute and chronic gastroenteritis, bacillary dysentery, typhoid and paratyphoid, etc.), urinary tract infections (gonorrhea, urethritis, cystitis, etc.), soft tissue infections and sepsis, meningitis, endocarditis, etc.

This product is a broad-spectrum semi-synthetic cephalosporin antibiotic. Its activity against penicillinase-producing Staphylococcus aureus, group A hemolytic streptococci, grass-green streptococci and Staphylococcus epidermidis is the same as that of cefadroxil, and its antibacterial effect against non-enzyme-producing Staphylococcus aureus and pneumococci is 2-4 times stronger than that of cefadroxil. Its activity against Gram-negative bacilli, including Escherichia coli and Klebsiella pneumoniae, is stronger than that of cefadroxil, and is similar to that of cefadroxil. Its activity against Proteus mirabilis, Salmonella and Shigella is stronger than that of cefadroxil. 9-8 mg/L of this product can inhibit all Haemophilus influenzae, including strains resistant to ampicillin. Moraxella catarrhalis and Neisseria gonorrhoeae are very sensitive to this product. Indole-positive Proteus, Serratia, Acinetobacter and Pseudomonas aeruginosa are all resistant to this product. The mechanism of action of this product is to inhibit the synthesis of bacterial cell walls.