Antimicrobial drugs acting extracellularly i. Cell wall synthesis inhibitors Beta-lactams (penicillin, cephem, carbapenem, and monobactam)
ii. Cell membrane dysfunction drugs Cyclic peptides (polymixin and bacitracin)
Antimicrobial drugs acting intracellularly iii. Nucleic acid dysfunction drugs:
Quinolones and rifamycin
iv. Protein synthesis inhibitors:
Macrolides, tetracycline, aminoglycosides and chloramphenicol
v. Folic acid synthesis inhibitor:
Sulfa drugs, trimethoprim and ST combination drug
Table 1: Classification of major antimicrobial drugs by mechanism of action.