| Severe: Piperacillin-tazobactam 3.375 grams IV every 6 hours  OR | 
| Ticarcillin-clavulanic acid 3.1 grams IV every 6 hours OR | 
| Doripenem 500 mg IV q8h OR Meropenem 1 gm IV q8h OR
 Imipenem 500mg IV every 6 hours.  OR
 | 
| [Ciprofloxacin 400mg ivpb q12h or Levofloxacin 500mg ivpb qd] PLUS [Clindamycin 600mg ivpb q6-8h or Metronidazole 500mg ivpb q6-8h.] | 
| Ceftazidime 1-2 grams IV every 8 hours  OR Cefepime 1-2 grams q 12h PLUS  Metronidazole 500mg ivpb q6-8h.
 | 
| Penicillin allergic:   |