STUDY OF CEFIXIME BILIARY CLEARANCE IN CH OLECYSTECTOMIZED PATIENTS

Cefixime is an orally administered cephalosporin with physicochemical properties able to account for a possibly significant biliary excretio n. In addition, over 50 % of total clearance of the drug has been show n to operate through extra renal pathways in healthy volunteers. The a im of the study was to quantify and to delineate the kinetics of cefix ime biliary elimination in ten patients provided with external drainag e. Following a single 200 mg oral dose of cefixime, biliary clearance of the drug appears to vary from 0.85 to 27.3 ml/min. Contribution of the latter to the apparent total clearance is relatively low since ran ging from 0.8 to 18.6 % (mean 5 %). Additionaly, biliary clearance kin etics of the drug proves non linear and well described according to a sigmoidal model. On account of these results, and given the dianionic charge of the molecule as well as the absence of any metabolite report ed so far, an intrahepatic binding and accumulating process, mediated by ligandin, seems to underlie the hepatobiliary excretion of cefixime , as previously reported for other anionic betalactam antibiotics.