Antimicrobial Therapy That Is Typically Active Against Commonly Encountered Anaerobes | |
| ANTIBIOTIC(S) | CAVEATS |
|---|---|
| Metronidazole | This drug is clinically unreliable against gram-positive non-spore-forming anaerobes (e.g., Actinomyces spp., Propionibacterium spp., Peptostreptococcus spp.). |
| β-Lactam/β-lactamase inhibitor combinations (ampicillin-sulbactam, ticarcillin-clavulanic acid, piperacillin-tazobactam) | Rates of resistance are increasing in some gram-negative anaerobes. The newer cephalosporin/β-lactamase combinations have limited anaerobic activity. |
| Clindamycin | Rates of resistance are increasing in Bacteroides spp. |
| Carbapenems (meropenem, imipenem, ertapenem, doripenem) | Rates of resistance are currently very low (<5%), although some carbapenemase-producing strains have been identified. |
| Chloramphenicol | Some clinical failures have been noted, even when the isolate is found to be susceptible by in vitro testing. |