Piperacillin%25252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252520tazobactam%25252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252520%25252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252528zosyn%25252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252529

# Piperacillin/Tazobactam (Zosyn) ## Overview Piperacillin/tazobactam is an extended-spectrum penicillin antibiotic combined with a beta-lactamase inhibitor. ## Primary Indications * **Complicated intra-abdominal infections (cIAI)** * **Complicated skin and skin structure infections (cSSSI)** * **Community-acquired pneumonia (CAP)** * **Hospital-acquired pneumonia (HAP)** and **Ventilator-associated pneumonia (VAP)** Piperacillin/tazobactam is active against many Gram-positive, Gram-negative (including *Pseudomonas aeruginosa*), and anaerobic bacteria. ## Adult Dosing Standard dosing for **complicated intra-abdominal infections, complicated skin and skin structure infections, community-acquired pneumonia, hospital-acquired pneumonia, and ventilator-associated pneumonia** is: * **3.375 grams IV every 6 hours** OR * **4.5 grams IV every 6 or 8 hours** The choice between 3.375 g and 4.5 g, and the 6-hour or 8-hour interval for 4.5 g, depends on the specific indication, severity of infection, and local institutional guidelines or prescribing information. Higher doses and/or more frequent administration may be used for severe infections, particularly those involving *Pseudomonas aeruginosa*. Duration of therapy varies by indication and clinical response, typically ranging from 4 to 14 days. ## Pediatric Dosing Dosing for pediatric patients (3 months and older) is based on piperacillin component weight-based dosing: * **For cIAI, cSSSI, CAP, HAP, VAP:** * **75 mg/kg (piperacillin component) IV every 6 hours** * Maximum piperacillin dose: 4 grams per dose. * Maximum tazobactam dose: 0.5 grams per dose. Consider the piperacillin:tazobactam ratio (typically 8:1). ## Dose Adjustments * **Renal Impairment:** * CrCl ≥ 40 mL/min: No adjustment needed. * CrCl 20-39 mL/min: Administer the usual dose every 8 hours. * CrCl < 20 mL/min: Administer the usual dose every 12 hours. * For patients on intermittent hemodialysis, administer the usual dose every 12 hours and administer an additional 0.75 g dose after each dialysis session. * **Hepatic Impairment:** No dose adjustment is generally recommended, but caution is advised. ## Contraindications * Known history of severe allergic reaction to penicillins, cephalosporins, beta-lactamase inhibitors, or any component of the formulation. ## Adverse Effects * **Common:** Diarrhea, nausea, vomiting, headache, rash, pruritus, insomnia, fever, thrombophlebitis. * **Serious:** * Hypersensitivity reactions (including anaphylaxis) * *Clostridioides difficile*-associated diarrhea (CDAD) * Seizures (especially with high doses or renal impairment) * Hematologic effects (e.g., neutropenia, thrombocytopenia) * Hepatotoxicity ## Key Drug Interactions * **Probenecid:** May increase and prolong piperacillin/tazobactam serum concentrations. * **Neuromuscular blocking agents (e.g., vecuronium):** Piperacillin may prolong the effect of vecuronium. * **Warfarin:** Piperacillin may decrease warfarin's anticoagulant effect. Monitor INR closely. * **Live attenuated bacterial vaccines:** Piperacillin/tazobactam may reduce the efficacy of these vaccines. ## Monitoring * Renal function * Liver function tests * Complete blood count (CBC) * Electrolytes * Signs and symptoms of infection * Signs of hypersensitivity reactions * For patients on warfarin, monitor INR closely. ## Clinical Pearls * Piperacillin/tazobactam is a broad-spectrum agent often used empirically for serious bacterial infections. * De-escalation to a narrower-spectrum agent should be considered once culture and sensitivity results are available. * Ensure adequate hydration when reconstituting and administering the drug, as it is associated with thrombophlebitis. * The 3.375 g formulation contains 3 g piperacillin and 0.375 g tazobactam. The 4.5 g formulation contains 4 g piperacillin and 0.5 g tazobactam. * Reconstituted solutions are typically administered as a continuous infusion over 30 minutes. *** **Disclaimer:** This information is intended for healthcare professionals and is not a substitute for professional medical advice. Always consult the most current prescribing information and local protocols before administering any medication.