Piperacillin/tazobactam  (PDF Version)


Antibiotic Class:

Beta-lactam/beta-lactamase inhibitor


Antimicrobial Spectrum:

Staphylococcus aureus (methicillin susceptible), Coagulase negative Staphylococci, Streptococcus pneumoniae (penicillin susceptible), Streptococcus spp., Haemophilus influenzae, Moraxella catarrhalis, Neisseria meningitides, Neisseria gonorrhoeae, Enterobacteriaceae, E. coli, Pseudomonas aeruginosa


Mechanism of Action:

The beta-lactamase inhibitors are recognized as substrates for the beta-lactamases produced by bacteria. This allows the actual beta-lactams to attack the bacterial cell wall by binding to penicillin binding proteins



Time dependent killer (Time > MIC)



(of the tazobactam)

Dose 200mg: Cmax: 29 mcg/L; Protein binding: 20-23%; Volume of distribution: 0.18-0.33L/kg; Table 5


Adverse Effects:

No new adverse effects are seen as a result of adding beta-lactamase inhibitors to beta-lactam antibiotics. The adverse reactions would remain the same for the parent compound



IV: Complete listing on Table 6


Dosing in adults:

Mild/Moderate: 2.25-3.375g q6h

Severe: 3.375-4.5g q6h


Dosing in pediatrics:

Not indicated in children < 12 years of age

Table 8


Disease state based dosing:

Renal failure:  CrCl > 40mL/min: 3.375g q4-6h

                       CrCl 20-40mL/min: 2.25g q6h

                       CrCl < 20mL/min: 2.25g q8h


Hepatic failure:  Dosage adjustment not necessary

Table 9


Dosing during Continuous Renal Replacement Therapy

CVVH (Continuous venovenous hemofiltration): 2.25g IV q6h

CVVHD (Continuous venovenous hemodialysis): 2.25-3.375g IV q6h

CVVHDF (Continuous venovenous hemodiafiltration) 2.25g-3.375g IV q6h

Note: CVVH is mainly for fluid removal alone. Many institutions will employ more CVVHD or CVVHDF which combine dialysis with fluid removal.



Precautions:  hypersensitivity to penicillins, history of gastrointestinal disease, particularly colitis, renal impairment


Drug Interactions:

Live Typhoid Vaccine - decreased immunological response to the typhoid vaccine

Methotrexate increased methotrexate toxicity

Probenecid - increased piperacillin levels

Vecuronium - enhanced and/or prolonged neuromuscular blockade which may lead to respiratory depression and paralysis



Category B: No evidence of risk in humans but studies inadequate.


Monitoring Requirements:

Therapeutic:  Culture and sensitivities, serum levels, signs and symptoms of infection, white blood cell count

Toxic: Urinalysis, BUN, SCr, AST and ALT, skin rash, Neutropenia and leukopenia,


Brand names/Manufacturer:  Zosyn/Wyeth pharmaceuticals