Common antibiotic drugs are penicillin, amoxicillin, erythromycin, azithromycin, and cephalosporins. Antibiotics are mainly divided into the following categories. 1. β-lactams: including penicillins and cephalosporins, etc. Penicillins, such as penicillin G, ampicillin, carbenicillin, alloxacillin, melphalan, piperacillin, amoxicillin and so on. Cephalosporin antibiotics, there have been five generations, the main representative drugs are cefthiophene, cefradine, cefuroxime, cefaclor, ceftriaxone, ceftazidime, cefpirome, cefepime, ceflorin, cefotrol, cefepime and so on. 2. Aminoglycosides: the main representative drugs are gentamicin and butamidokanamycin. 3. Tetracyclines: common drugs are tetracycline and oxytetracycline. 4. Chloramphenicol: mainly chloramphenicol and methicillin. 5. macrolides: erythromycin and acetylspiramycin. 6. other classes of antibiotics that act on gram-positive bacteria: for example, vancomycin, which can be used for severe infections. 7. Other antibiotics: e.g. polymyxin and cyclosporine.