Please check your internet connection and try again.
# Piperacillin/Tazobactam (Zosyn)
## Overview
Piperacillin/tazobactam is a combination of an extended-spectrum penicillin-class antibacterial (piperacillin) and a beta-lactamase inhibitor (tazobactam). It is active against many Gram-positive, Gram-negative, and anaerobic bacteria.
## Primary Indications
* Complicated intra-abdominal infections
* Complicated skin and skin-structure infections
* Community-acquired pneumonia
* Hospital-acquired pneumonia (including ventilator-associated pneumonia)
## Adult Dosing
* **Standard Dose:** 3.375 grams (piperacillin 3 g / tazobactam 0.375 g) every 6 hours.
* **High Dose:** 4.5 grams (piperacillin 4 g / tazobactam 0.5 g) every 6 or 8 hours. Higher doses are typically used for more severe infections or those caused by less susceptible organisms.
* **Maximum Dose:** Generally 18 g per day (4.5 g every 6 hours).
Dosing frequency and duration depend on the type and severity of infection, pathogen susceptibility, and patient response.
## Pediatric Dosing
* **Children 0 to 12 months:** Not established due to safety concerns.
* **Children > 12 months:**
* **Intra-abdominal infections:** 100 mg piperacillin component per kg of body weight every 8 hours.
* **Other infections:** 80 mg piperacillin component per kg of body weight every 8 hours.
* **Maximum Dose:** Do not exceed the maximum adult dose of 4.5 g per dose or 18 g per day.
Tazobactam component dosing is typically calculated as 1/8th of the piperacillin dose. Renal dose adjustment is required for pediatric patients.
## Dose Adjustments
* **Renal Impairment (CrCl < 40 mL/min):**
* **CrCl 20-40 mL/min:** 2.25 g (piperacillin 2 g / tazobactam 0.25 g) every 6 hours.
* **CrCl < 20 mL/min:** 2.25 g (piperacillin 2 g / tazobactam 0.25 g) every 8 hours.
* **Hemodialysis:** 2.25 g (piperacillin 2 g / tazobactam 0.25 g) every 8 hours, with an additional 0.75 g dose after each dialysis session.
Adjustments are often based on total piperacillin/tazobactam content.
## Contraindications
* Known serious allergic reaction to piperacillin, other penicillinase-resistant penicillins, cephalosporins, or beta-lactamase inhibitors.
## Adverse Effects
* **Common:** Diarrhea, nausea, vomiting, rash, headache, insomnia, constipation, eosinophilia, elevated liver enzymes.
* **Serious:** *Clostridioides difficile*-associated diarrhea, hypersensitivity reactions (including anaphylaxis), seizures (especially with high doses or renal impairment), neutropenia, thrombocytopenia, interstitial nephritis, hepatitis.
## Key Drug Interactions
* **Probenecid:** May increase and prolong piperacillin/tazobactam serum concentrations.
* **Neuromuscular blocking agents:** Piperacillin may prolong the action of vecuronium.
* **Warfarin:** Monitor INR closely as piperacillin may decrease warfarin effect.
* **Methotrexate:** Piperacillin may decrease methotrexate clearance; monitor methotrexate levels.
## Monitoring
* Renal and hepatic function.
* Complete blood counts (especially if prolonged therapy).
* Signs and symptoms of hypersensitivity reactions.
* Signs and symptoms of *C. difficile*-associated diarrhea.
* Therapeutic drug monitoring is generally not indicated for piperacillin/tazobactam unless specific circumstances warrant (e.g., severe renal dysfunction, critical illness).
## Clinical Pearls
* Piperacillin/tazobactam is a broad-spectrum agent used for serious bacterial infections, including those involving resistant organisms.
* It has excellent activity against *Pseudomonas aeruginosa*.
* Ensure adequate hydration and monitor for signs of fluid overload, especially in patients with heart failure.
* When reconstituting, use the provided diluent or a compatible solution as per manufacturer instructions. Avoid dextrose solutions for reconstitution if the reconstituted solution is to be infused in a piggyback or Y-site.
***
**Disclaimer:** This information is intended for clinical pharmacy professionals and is not a substitute for professional medical advice. Always verify current prescribing information and consult with appropriate healthcare providers before making any treatment decisions. Dosing can vary significantly based on patient-specific factors and local institutional protocols.
