piperacillin and tazobactam (Zosyn)

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GENERIC NAME: piperacillin and tazobactam

BRAND NAME: Zosyn

DRUG CLASS AND MECHANISM: Zosyn is an injectable combination of two antibiotics, piperacillin and tazobactam, with broad spectrum activity against an extended range of bacterial species. Piperacillin is an extended-spectrum penicillin antibiotic, but it can be destroyed by an enzyme produced by bacteria called beta lactamase. Tazobactam inhibits beta lactamase and prevents the destruction of piperacillin. Therefore, tazobactam is given with piperacillin to enhance the activity of piperacillin in eradicating bacterial infections.

Piperacillin kills bacteria by inhibiting the synthesis of bacterial cell walls. It binds preferentially to specific penicillin-binding proteins (PBPs) located inside bacterial cell walls. PBPs vary among bacterial species, and thus susceptibility to piperacillin depends on the ability of piperacillin to bind to each species' specific PBPs.

In-vitro studies of piperacillin and tazobactam have shown that the combination has activity against a variety of gram-positive and gram-negative aerobic and anaerobic bacteria.

Susceptible bacteria include:

  • Aerobic and facultative gram-positive microorganisms: Staphylococcus aureus
  • Aerobic and facultative gram-negative microorganisms: Acinetobacter baumannii, Escherichia coli, Haemophilus influenzae, Klebsiella pneumoniae, and Pseudomonas aeruginosa
  • Gram-negative anaerobes: Bacteroides fragilis group (B.fragilis, B. ovatus, B. thetaiotaomicron, and B. vulgatus)
  • Piperacillin and tazobactam was approved by the US Food and Drug Administration (FDA) in October 1993.
Medically Reviewed by a Doctor on 12/12/2014



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