Transfer of piperacillin to various uterine tissues. Piperacillin study group for application in the field of obstetrics and gynecology.

As part of our series of fundamental studies on the application of piperacillin (PIPC) in the gynecologic field, we studied the transfer of PIPC to the uterine tissues. During our pharmacokinetic study of PIPC, a two-compartment model was used for blood levels: C1 = Ae-beta t + Be-alpha t. A three-compartment model was applied for the levels in the various uterine tissues and the retroperitoneum; C3 = A'e-beta t + B'e-alpha t + Ce-K31t. PIPC showed rapid transfer to the various uterine tissues and its disappearance rate developed parallel to decreases in blood concentrations. Although its transfer to the retroperitoneum was relatively rapid, since there was a clear delay in time required for the drug concentration to reach its peak (C max), the existence of a third compartment was conjectured. From the correlation between the MIC80 and the drug concentrations in the various uterine tissues and the retroperitoneum, it was found that effective doses were maintained in the uterine tissues for 3-5 h and in the retroperitoneum for 8-19 h. Thus, adequate clinical efficacy could be anticipated during administration of PIPC.