Zosyn (Piperacillin/Tazobactam) Treatment and Dosage Recommendations
For adult patients with infections, Zosyn (piperacillin/tazobactam) should be administered at a dose of 3.375 g every 6 hours intravenously for most infections, or 4.5 g every 6 hours for nosocomial pneumonia, with dosage adjustments required for renal impairment. 1
Adult Dosing Recommendations
Standard Dosing
- Most infections: 3.375 g IV every 6 hours (totaling 13.5 g/day) administered over 30 minutes 1
- Nosocomial pneumonia: 4.5 g IV every 6 hours (totaling 18 g/day) plus an aminoglycoside 1
- Treatment duration: 7-10 days for most infections; 7-14 days for nosocomial pneumonia 1
Renal Impairment Dosing
| Creatinine Clearance | Standard Infections | Nosocomial Pneumonia |
|---|---|---|
| >40 mL/min | 3.375 g q6h | 4.5 g q6h |
| 20-40 mL/min | 2.25 g q6h | 3.375 g q6h |
| <20 mL/min | 2.25 g q8h | 2.25 g q6h |
| Hemodialysis | 2.25 g q12h* | 2.25 g q8h* |
| CAPD | 2.25 g q12h | 2.25 g q8h |
*Additional 0.75 g dose should be administered following each hemodialysis session 1
Pediatric Dosing
For children 2 months and older, weighing up to 40 kg:
| Age | Appendicitis/Peritonitis | Nosocomial Pneumonia |
|---|---|---|
| 2-9 months | 90 mg/kg (80/10) IV q8h | 90 mg/kg (80/10) IV q6h |
| >9 months | 112.5 mg/kg (100/12.5) IV q8h | 112.5 mg/kg (100/12.5) IV q6h |
Children >40 kg should receive adult dosing 1
Indications
Zosyn is FDA-approved for the treatment of:
- Intra-abdominal infections (appendicitis, peritonitis) 1
- Nosocomial pneumonia 1
- Skin and skin structure infections (cellulitis, abscesses, diabetic foot infections) 1
- Female pelvic infections (postpartum endometritis, PID) 1
- Community-acquired pneumonia (moderate severity) 1
Specific Clinical Scenarios
Skin and Soft Tissue Infections
- For complicated skin/soft tissue infections, Zosyn is effective as monotherapy at 3.375 g every 6 hours or 4.5 g every 8 hours IV 2
- For necrotizing infections, Zosyn can be used as part of broad-spectrum coverage (often combined with vancomycin or linezolid for MRSA coverage) 2
Intra-abdominal Infections
- Zosyn is effective as monotherapy for most intra-abdominal infections 2, 1
- For healthcare-associated or nosocomial infections, consider local resistance patterns 2
Nosocomial Pneumonia
- Higher dosing (4.5 g every 6 hours) plus an aminoglycoside is recommended 1
- Continue aminoglycoside in patients with confirmed Pseudomonas aeruginosa 1
Multidrug-Resistant Organisms
- For carbapenem-resistant Pseudomonas aeruginosa (CRPA) susceptible to piperacillin/tazobactam: 3.375-4.5 g IV q6h 2
- For difficult-to-treat Pseudomonas, combination therapy may be needed 2
Administration Considerations
- Administer by IV infusion over 30 minutes 1
- For patients with high MIC pathogens, prolonged infusion of β-lactams is recommended 2
- Consider infectious disease consultation for management of infections caused by multidrug-resistant organisms 2
Common Pitfalls and Caveats
- Renal dosing: Failure to adjust dosing in renal impairment can lead to toxicity 1
- Resistance concerns: Local antibiograms should guide therapy, especially for healthcare-associated and nosocomial infections 2
- Inadequate dosing: Underdosing may lead to treatment failure, particularly with high-MIC pathogens 2
- Combination therapy: For severe infections or suspected Pseudomonas, combination therapy may be necessary 1
- Duration: Avoid unnecessarily prolonged courses; 7-10 days is typically sufficient for most infections 1
For infections caused by suspected or confirmed multidrug-resistant organisms, infectious disease consultation is strongly recommended to optimize therapy and improve outcomes 2.