摘要:Ten healthy volunteers were given 250 mg cefuroxime-axetil tablets b.i.d. for 10 d. Stool samples were collected before, during and after cefuroxime-axetil administration. The mean concentrations of cefuroxime in faeces on days 7 and 10 were 0.57 mg/kg (range < 0.125-0.84 mg/kg) and 0.48 mg/kg (range <0.125-1.35 mg/kg) respectively. There was an overgrowth of enterococci and staphylococci, while the levels of bacilli and enterobacteria were not significantly altered during the administration period. Six subjects became colonised by Candida albicans and three by Clostridium difficile during and after the administration period. Two of the volunteers with C. difficile reported mild diarrhoea during the administration period. The number of bifidobacteria and clostridia decreased while the levels of eubacteria and bacteroides were unaffected by cefuroxime-axetil administration. β-Lactamase activities in faeces were found in six volunteers and increased significantly during the administration period (P<0.05). There was a clear relationship between β-lactamase activities in faeces, concentrations of cefuroxime and alterations in the normal microflora. Low cefuroxime concentrations in faeces corresponded to highβ -lactarnase activities and minor alterations in the normal microflora, while high cefuroxime concentrations in faeces corresponded to low β-lactamase activities and considerable ecological disturbances in the faecal microflora.Keywords - Oral cephalosporin, Cefuroxime-axetil, Normal faecal microflora, Clostridium difficile, β-lactamase.