Antibiotic Classification by Mechanism of Action

Inhibition of Cell Wall Synthesis

• Beta-lactam antibiotics inhibit cell wall synthesis
• Penicillins are classified into natural penicillins, antistaphylococcal penicillins, aminopenicillins, broad spectrum penicillins, and anti-pseudomonal penicillins
• Cephalosporins are classified into five generations (1st to 5th)

Inhibition of Protein Synthesis

• 30S inhibitors: tetracyclines, glycylcyclines, and aminoglycosides act on the 30S ribosomal subunit
• 50S inhibitors: macrolides, ketolides, macrocyclic, chloramphenicol, oxazolidinones, lincosamides, and streptogramins act on the 50S ribosomal subunit

Inhibition of Nucleic Acid Synthesis

• Topoisomerases inhibit DNA synthesis
• Quinolones, including second, third, and fourth generations, and fluoroquinolones, also inhibit nucleic acid synthesis

Other Mechanisms

• Antifolates, including DHFR inhibitors and CO, inhibit folate synthesis
• Monobactams, carbapenems, and glycopeptide antibiotics have unique mechanisms of action
• Other antibiotics with distinct mechanisms include methicillin, nafcillin, and oxacillin

Antibiotics

• List of penicillin-based antibiotics: penicillin G, procaine penicillin G, benzathine penicillin G, methicillin, nafcillin, and others
• List of cephalosporin-based antibiotics: cefadroxil, cephalexin, cefradine, cefazolin, and many others
• List of carbapenem-based antibiotics: imipenem, meropenem, doripenem
• List of monobactam-based antibiotics: aztreonam