Concept
Piperacillin/tazobactam, sold under the brand name Zosyn among others, is a combination medication containing the antibiotic piperacillin and the β-lactamase inhibitor tazobactam. The combination has activity against many Gram-positive and Gram-negative bacteria including Pseudomonas aeruginosa. It is used to treat pelvic inflammatory disease, intra-abdominal infection, pneumonia, cellulitis, and sepsis. It is given by injection into a vein. Common adverse effects include headache, trouble sleeping, rash, nausea, constipation, and diarrhea. Serious adverse effects include Clostridium difficile infection and allergic reactions including anaphylaxis. Those who are allergic to other β-lactam are more likely to be allergic to piperacillin/tazobactam. Use in pregnancy or breastfeeding appears to generally be safe. It usually results in bacterial death through blocking their ability to make a cell wall. Piperacillin/tazobactam was approved for medical use in the United States in 1993. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication. Its main uses are in intensive care medicine (pneumonia, peritonitis), some diabetes-related foot infections, and empirical therapy in febrile neutropenia (e.g., after chemotherapy). The drug is administered intravenously every 6 or 8 hr, typically over 3–30 min. It may also be administered by continuous infusion over four hours. Prolonged infusions are thought to maximize the time that serum concentrations are above the minimum inhibitory concentration (MIC) of the bacteria implicated in infection. Piperacillin-tazobactam is recommended by the National Institute for Health and Care Excellence as first-line therapy for the treatment of bloodstream infections in neutropenic cancer patients. For β-lactam antipseudomonal antibiotics, including piperacillin/tazobactam, prolonged intravenous infusion is associated with lower mortality than bolus intravenous infusion in persons with sepsis due to Pseudomonas aeruginosa.