Please check your internet connection and try again.
# Piperacillin-Tazobactam (Zosyn)
## Overview
Piperacillin-tazobactam is a combination penicillin-class antibacterial and beta-lactamase inhibitor.
## Primary Indications
* Complicated intra-abdominal infections
* Complicated skin and skin structure infections
* Hospital-acquired pneumonia (including ventilator-associated pneumonia)
* Febrile neutropenia (empiric treatment)
* Community-acquired pneumonia
* Pyelonephritis
## Adult Dosing
Standard doses are:
* **3.375 g IV every 6 hours** (Piperacillin 3 g / Tazobactam 0.375 g)
* **4.5 g IV every 6 hours** (Piperacillin 4 g / Tazobactam 0.5 g)
Higher doses may be used for severe infections or those caused by less susceptible organisms, typically up to **4.5 g IV every 4 hours**. Dosing frequency and duration depend on the indication, severity of illness, and patient response.
## Pediatric Dosing
Dosing is based on piperacillin component, usually administered every **6 or 8 hours**:
* **< 2 months:** Data is limited; consult specialized resources.
* **≥ 2 months:** 100 mg piperacillin/kg/dose IV every 6 hours or 75 mg piperacillin/kg/dose IV every 8 hours.
* **Maximum dose:** Do not exceed the maximum adult dose of 4.5 g every 4 hours.
## Dose Adjustments
**Renal Impairment:**
* CrCl ≥ 40 mL/min: No adjustment needed.
* CrCl 20-39 mL/min: 2.25 g IV every 6 hours or 3.375 g IV every 8 hours.
* CrCl < 20 mL/min: 2.25 g IV every 8 hours.
* Hemodialysis: Administer dose after dialysis and supplement with an additional 0.75 g dose.
**Hepatic Impairment:** No dose adjustment is generally required.
## Contraindications
* Known severe hypersensitivity to piperacillin, tazobactam, other penicillinase-resistant penicillins, or beta-lactamase inhibitors.
## Adverse Effects
Common: Diarrhea, nausea, vomiting, rash, headache, insomnia, fever, constipation, abdominal pain.
Serious: *Clostridioides difficile*-associated diarrhea, hypersensitivity reactions (including anaphylaxis), seizures (especially with high doses or renal impairment), hepatotoxicity, neutropenia, thrombocytopenia, prolonged prothrombin time.
## Key Drug Interactions
* **Probenecid:** May increase and prolong piperacillin-tazobactam plasma concentrations.
* **Neuromuscular blocking agents (e.g., vecuronium):** May prolong neuromuscular blockade.
* **Warfarin:** May decrease the effect of warfarin; monitor INR closely.
* **Methotrexate:** May decrease methotrexate clearance; monitor methotrexate levels.
## Monitoring
* Renal function (especially with dose adjustments).
* Signs and symptoms of hypersensitivity reactions.
* Signs and symptoms of *C. difficile*-associated diarrhea.
* Complete blood count (CBC) with differential and platelet count, especially with prolonged therapy.
* Liver function tests (LFTs).
* Prothrombin time (PT)/International Normalized Ratio (INR) if co-administered with warfarin.
## Clinical Pearls
* Reconstituted solution should be diluted further for IV infusion.
* Infusion rates are critical to minimize adverse effects; typically administered over 30 minutes. Faster infusions can increase the risk of seizures.
* Tazobactam protects piperacillin from degradation by many beta-lactamase enzymes.
***
*This information is intended for clinical decision-making support and does not replace comprehensive drug reference materials. Always verify current prescribing information, including dosage, administration, contraindications, and warnings, with official product labeling or a trusted drug information resource before administration.*
