| Criteria | Bactericidal Antibiotics | Bacteriostatic Antibiotics | Remarks |
| Definition | Kill bacteria directly by targeting vital processes | Inhibit bacterial growth and reproduction without directly killing the cells | Fundamental difference lies in the mode of action |
| Mechanism of Action | Disrupt essential functions such as cell wall synthesis, DNA replication, or membrane integrity | Inhibit protein synthesis or metabolic pathways necessary for bacterial proliferation | Bactericidal actions are typically more aggressive and faster-acting |
| Examples | Penicillin, Cephalosporins, Fluoroquinolones, Aminoglycosides | Tetracyclines, Macrolides, Sulfonamides, Chloramphenicol | Drug choice depends on pathogen, infection site, and host immune status |
| Dependence on Immune System | Less reliant on host immune system to eliminate pathogens | Heavily reliant on a functioning immune system to clear inhibited bacteria | Bacteriostatic drugs may not be ideal in immunocompromised patients |
| Effectiveness in Severe Infections | Preferred for life-threatening or invasive infections | May be inadequate for severe infections | Clinical decisions often favor bactericidal agents in critical cases |
| Post-Antibiotic Effect | Often have a strong post-antibiotic effect | Generally weaker or minimal post-antibiotic effect | Important in maintaining bacterial suppression after drug clearance |
| Resistance Development | May promote resistance if killing is incomplete or through mutation | May allow survival of dormant cells, promoting resistance upon prolonged use | Both require careful stewardship to prevent antimicrobial resistance |
