PENETRATION OF CEFETAMET PIVOXIL AND CEFUROXIME AXETIL INTO THE MAXILLARY SINUS MUCOSA AT STEADY-STATE

The penetration of cefetamet and cefuroxime into the maxillary sinus m ucosa after the administration of cefetamet pivoxil and cefuroxime axe til was investigated in patients undergoing elective surgery of the ma xillary sinus. A total of 27 patients, 13 for cefetamet pivoxil and 13 for cefuroxime axetil, ranging from 15 to 70 years of age participate d in this study. Each patient received three oral doses of either one tablet of cefetamet pivoxil (500 mg of GLOBOCEF) or two film tablets o f cefuroxime axetil (125 and 250 mg of ZINAT) every 12 h. Sinus mucosa tissue samples were removed during surgery at times ranging from 2 to 4.5 h after the last oral administration, flood samples were collecte d before drug administration, 2 h after the first and third doses, and concomitantly with tissue sample collection during surgery. All sampl es were analyzed by high-performance liquid chromatography. The concen trations of cefetamet and cefuroxime in plasma samples measured concom itantly with those in tissue samples ranged between 0.83 and 4.5 mu g/ ml for cefetamet and 0.59 and 3 mu g/ml for cefuroxime. The mean tissu e-to-plasma ratios calculated with reference to total (bound plus unbo und) plasma drug concentrations were 0.60 (range, 0.52 to 0.77) for ce fetamet (n = 4) and 0.38 (range, 0.28 to 0.44) for cefuroxime (n = 6). Both drugs seem to penetrate freely and easily into the sinus mucosa. The antibacterial activities of cefetamet pivoxil and cefuroxime axet il in cases of sinusitis therefore depend mainly on their achieved act ive plasma drug concentrations and their intrinsic activities in inhib iting the causative organism(s).