What is the usage and dosage of Zosyn (piperacillin and tazobactam)?

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From the Guidelines

Zosyn (piperacillin-tazobactam) should be dosed at 3.375g (3g piperacillin/0.375g tazobactam) administered intravenously every 6 hours for most adult infections, as recommended by the most recent guidelines 1.

Usage and Dosage

The usage and dosage of Zosyn (piperacillin and tazobactam) are as follows:

  • For most adult infections, the dose is 3.375g every 6 hours, which can be increased to 4.5g every 6 hours for more severe infections, such as Pseudomonas aeruginosa infection 1.
  • Treatment duration generally ranges from 7-14 days depending on the type and severity of infection.
  • Dosage adjustments are necessary for patients with renal impairment; for creatinine clearance 20-40 mL/min, the recommended dose is 2.25g every 6 hours, and for clearance below 20 mL/min, 2.25g every 8 hours is appropriate.
  • Each dose should be infused over 30 minutes.
  • For pediatric patients, the typical dose is 100 mg piperacillin/12.5 mg tazobactam per kg every 8 hours.

Mechanism of Action and Side Effects

Zosyn is a broad-spectrum antibiotic combination that works by inhibiting bacterial cell wall synthesis (piperacillin) while the tazobactam component protects piperacillin from degradation by beta-lactamase enzymes, making it effective against many resistant organisms 1. Common side effects include:

  • Diarrhea
  • Headache
  • Insomnia
  • Nausea Patients should be monitored for allergic reactions, especially those with penicillin allergies.

Key Considerations

When using Zosyn, it is essential to consider the following:

  • Serum drug-concentration monitoring should be considered for dosage individualization, especially in patients with renal impairment 1.
  • Initial dosage regimens for vancomycin should be based on total body weight, and for aminoglycosides, initial dosage regimens should be based on adjusted body weight 1.

From the FDA Drug Label

The usual total daily dosage of piperacillin and tazobactam for injection for adult patients with indications other than nosocomial pneumonia is 3.375 g every six hours [totaling 13.5 g (12 g piperacillin and 1.5 g tazobactam)], to be administered by intravenous infusion over 30 minutes. Initial presumptive treatment of adult patients with nosocomial pneumonia should start with piperacillin and tazobactam for injection at a dosage of 4.5 g every six hours plus an aminoglycoside, [totaling 18 g (16 g piperacillin and 2 g tazobactam)], administered by intravenous infusion over 30 minutes. The recommended daily dosage of piperacillin and tazobactam for injection for patients with renal impairment administered by intravenous infusion over 30 minutes is described in Table 1 The recommended dosage for pediatric patients with appendicitis and/or peritonitis or nosocomial pneumonia aged 2 months of age and older, weighing up to 40 kg, and with normal renal function, is described in Table 2

The usage and dosage of Zosyn (piperacillin and tazobactam) are as follows:

  • Adult patients with indications other than nosocomial pneumonia: 3.375 g every 6 hours, totaling 13.5 g per day
  • Adult patients with nosocomial pneumonia: 4.5 g every 6 hours, plus an aminoglycoside, totaling 18 g per day
  • Pediatric patients:
    • 2 months to 9 months: 90 mg/kg every 8 hours for appendicitis and/or peritonitis, and 90 mg/kg every 6 hours for nosocomial pneumonia
    • Older than 9 months: 112.5 mg/kg every 8 hours for appendicitis and/or peritonitis, and 112.5 mg/kg every 6 hours for nosocomial pneumonia
  • Renal impairment: dosage reduction based on the degree of renal impairment, as described in Table 1 2

From the Research

Usage of Zosyn

  • Zosyn, a combination of piperacillin and tazobactam, is used to treat various bacterial infections, including lower respiratory tract, intra-abdominal, urinary tract, gynaecological, and skin/soft tissue infections 3.
  • It is also effective in treating fever in patients with neutropenia 3, 4.
  • The combination is useful for the treatment of patients with polymicrobial infections caused by aerobic or anaerobic beta-lactamase-producing bacteria 3.

Dosage of Zosyn

  • The typical dosage of Zosyn is 4 g/500 mg every 8 hours, administered intravenously 5, 6.
  • The dose ratio of piperacillin to tazobactam is 8:1 3, 4.

Efficacy of Zosyn

  • Clinical trials have demonstrated that Zosyn is effective in treating various infections, with clinical response rates ranging from 83.6% to 86% 5, 6.
  • Bacteriological response rates have also been high, with eradication rates of 73% to 85.3% 5, 6.
  • Zosyn has been shown to be as effective as or more effective than other antibiotics, such as ticarcillin/clavulanic acid and imipenem/cilastatin, in certain infections 3.

Safety and Tolerability of Zosyn

  • Zosyn is generally well tolerated, with the most common adverse events being gastrointestinal symptoms and skin reactions 3, 7.
  • The incidence of adverse events is higher when Zosyn is given in combination with an aminoglycoside than when given as monotherapy 3.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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