1990 Volume 38 Issue 5 Pages 453-460
We studied the influence of meal and solvents on the therapeutic efficacy of quinolones and oral cephems. The serum concentration and ED50 of oral antimicrobial agents suspended in water or milk were determined in fasted or non-fasted mice.
When cefixime, ofloxacin or enoxacin was orally administered to fasted mice, the serum concentration of each drug was higher than when water was used as a solvent. In contrast, when cefpodoxime proxetil or ciprofloxacin was administered to non-fasted mice, the serum concentration was higher in fasted mice. When cefaclor was suspended in water, the serum concentration in non-fasted mice was higher than that in fasted mice, but in fasted mice it was higher than in non-fasted when milk was used as a solvent. These results affected the drugs' efficacy in mice systemically infected with Klebsiella pneumoniae, in whom Cmax correlated best with ED50. However, the ED50 of cephems suspended in milk was lower than that in cephems suspended in water.
