- Cefepime
- Meropenem
- Moderate-to-High expresser of inducible AmpC which can cause failure of penicillins, beta-lactam/beta-lactamase inhibitors, 1st-3rd generation cephalosporins, aztreonam, and ertapenem, despite in vitro susceptibility
Intrinsic resistance:
- Ampicillin
- Amoxicillin/clavulanate
- Ampicillin/sulbactam
- 1st & 2nd gen cephs (Cefazolin, Cephalothin, Cefuroxime)
- Cephamycins (Cefoxitin, Cefotetan)