Tazocin (Piperacillin/Tazobactam) Usual Dosage
For adults with normal renal function and serious infections, the standard dose is 3.375g IV every 6 hours (total 13.5g daily), administered as an extended infusion over 3-4 hours rather than a standard 30-minute bolus. 1, 2
Adult Dosing by Clinical Indication
Standard Infections (Intra-abdominal, UTI, Skin/Soft Tissue, Gynecologic)
- 3.375g IV every 6 hours (total 13.5g daily) administered over 3-4 hours 1, 2
- This provides 12g piperacillin and 1.5g tazobactam daily 1
Nosocomial Pneumonia and Severe Pseudomonal Infections
- 4.5g IV every 6 hours (total 18g daily) administered over 3-4 hours 1, 2
- This provides 16g piperacillin and 2g tazobactam daily 1
- The higher dose is critical for infections with elevated MICs or Pseudomonas aeruginosa 2, 3
- Should be combined with an aminoglycoside for initial empiric therapy of nosocomial pneumonia 1
Extended Infusion Rationale
Extended infusion over 3-4 hours is strongly preferred over standard 30-minute infusions because:
- Beta-lactams exhibit time-dependent killing, requiring plasma concentrations above the MIC for 60-70% of the dosing interval for moderate infections and ideally 100% for severe infections 2, 3
- Meta-analyses demonstrate reduced mortality (RR 0.70) in critically ill septic patients receiving extended/continuous infusions versus intermittent bolus 2
- Patients with APACHE II ≥20 show particular benefit with improved clinical cure rates 2
Pediatric Dosing (≥2 Months of Age)
Children 2-9 Months
- Appendicitis/Peritonitis: 90 mg/kg (80 mg piperacillin/10 mg tazobactam) every 8 hours 1
- Nosocomial Pneumonia: 90 mg/kg every 6 hours 1
Children >9 Months (up to 40 kg)
- Appendicitis/Peritonitis: 112.5 mg/kg (100 mg piperacillin/12.5 mg tazobactam) every 8 hours 1
- Nosocomial Pneumonia: 112.5 mg/kg every 6 hours 1
Alternative Pediatric Dosing Framework
- 200-300 mg/kg/day of piperacillin component divided every 6-8 hours for complicated intra-abdominal infections 4
- Maximum doses should not exceed adult dosing 4
Renal Impairment Dosing
Creatinine Clearance ≤40 mL/min
- Dosage reduction is required based on degree of renal impairment 1, 5
- Loading doses remain unchanged; only maintenance doses require adjustment 2
Hemodialysis
- Hemodialysis removes 31% of piperacillin and 39% of tazobactam 5
- Supplemental dosing after dialysis sessions is necessary 5
Continuous Renal Replacement Therapy (CRRT)
- Therapeutic drug monitoring is strongly recommended due to significant pharmacokinetic variability 2
- Patients with residual CrCl >50 mL/min may have fivefold higher clearance compared to those with CrCl <10 mL/min, even while on CRRT 2
Critical Care and Septic Shock Considerations
Loading Dose Strategy
- Administer 4.5g as the first dose over 3-4 hours to rapidly achieve therapeutic levels in patients with expanded extracellular volume from fluid resuscitation 2
- Loading doses are not affected by renal function 2
Maintenance Dosing
- 4.5g every 6 hours as extended infusion for septic shock 2, 3
- Target piperacillin trough concentration of 33-64 mg/L for optimal outcomes 2
- Consider therapeutic drug monitoring within 24-48 hours in critically ill patients 2
Common Pitfalls to Avoid
Do not use standard 30-minute infusions in critically ill or septic patients—this fails to maintain adequate drug concentrations throughout the dosing interval and is associated with worse outcomes 2
Do not underdose at 3.375g every 6 hours for sepsis or nosocomial pneumonia—this lower dose is appropriate for less severe community-acquired infections but inadequate for septic patients, especially with Pseudomonas risk 2
Do not reduce dosing frequency to every 8 hours based solely on clinical improvement—maintain appropriate frequency until treatment completion 3
Monitor renal function closely in critically ill patients—piperacillin/tazobactam is an independent risk factor for acute kidney injury in this population, particularly at higher doses (4.5g) 1, 6