Pharmacokinetics and Pharmacodynamics of High-Dose Piperacillin/Tazobactam in Obese Patients

Worldwide rates of obesity have doubled in the last 30 years, and obesity has been associated as a risk factor for hospital-acquired infections and increased occurrence of death in critically-ill patients. Piperacillin/tazobactam is a commonly prescribed antibiotic for critically ill patients with an infection, however, limited information exists for dosing this drug in obese patients. In these limited reports, standard doses of piperacillin/tazobactam given to the small number of obese patients resulted in lower blood concentrations, which could lead to inadequate killing of bacteria. The purpose of this study is to compare blood concentrations from standard piperacillin/tazobactam dosing compared to higher dosing regimens in obese patients. This study will also include information on the safety and tolerability of the higher dose regimens. The study investigators believe that the higher dosing regimen will produce adequate blood levels in obese patients and will not add any more risk of harm to obese patients receiving this higher dose.