What is piperacillin/tazobactam sodium-injection, and how does it work (mechanism of action)?

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.

What brand names are available for piperacillin/tazobactam sodium-injection?


Is piperacillin/tazobactam sodium-injection available as a generic drug?


Do I need a prescription for piperacillin/tazobactam sodium-injection?


What are the side effects of piperacillin/tazobactam sodium-injection?

Common side effects associated with piperacillin/tazobactam

  • diarrhea,
  • headache,
  • constipation,
  • nausea,
  • difficulty sleeping,
  • rash,
  • vomiting,
  • upset stomach,
  • itching,
  • stool changes,
  • fever,
  • agitation,
  • Candida (oral [thrush]

    genital yeast infeciton),

  • high blood pressure,
  • dizziness,
  • stomach pain,
  • chest pain,
  • edema,
  • anxiety,
  • rhinitis, and
  • shortness of breath.

Rare side effects occurring with a frequency of less than 1% are:

Which drugs or supplements interact with piperacillin/tazobactam sodium-injection?

  • Probenecid may inhibit the renal tubular secretion (elimination via the
    kidneys) of piperacillin/tazobactam. This may cause higher, prolonged blood
    levels of piperacillin/tazobactam. The half-life of piperacillin is prolonged by
    21% and the half-life of tazobactam by 71%.
  • Piperacillin/tazobactam may inhibit platelet aggregation (formation of a
    blood clot) which may increase the risk for bleeding. Co-administration with
    blood thinning agents such as
    warfarin (Coumadin) requires close monitoring for
    signs or symptoms of bleeding.
  • Piperacillin/tazobactam may prolong the neuromuscular blockade of vecuronium
  • Piperacillin/tazobactam may decrease the renal (kidney) elimination of
    methotrexate (Trexall). Patients on concurrent therapy with methotrexate should
    be monitored frequently for signs or symptoms of methotrexate toxicity.

Medically Reviewed by a Doctor on 5/15/2017

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