Ceftriaxone: pharmacokinetics and effect on the intestinal microflora in patients with acute bacterial infections.
12 patients with acute bacterial infections were treated with ceftriaxone, 1.5 g intravenously twice daily for 7-13 days. Pharmacokinetic variables were studied in 11 patients. In older subjects, serum half-lives were longer and serum clearances lower than in younger individuals. After the last dose, a larger increase in AUC compared to the first dose was observed in older patients and a biphasic elimination curve appeared in all patients but 2, with a terminal half-life of 15.6 h and 11.4 in old and young subjects, respectively. Estimated biliary clearances showed large individual variation, with a range of 0-16 ml/min X 1.73 m2. Changes in the colonic microflora were pronounced. Almost total disappearance of staphylococci, streptococci and enterobacteria was found, and there was a marked tendency to overgrowth of yeasts and enterococci. One patient with the highest estimated biliary clearance of ceftriaxone developed diarrhoea after 7 days of therapy. A toxin-producing Clostridium difficile was isolated from the stool.
D000208:Acute Disease; D000328:Adult; D000368:Aged; D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development; D001424:Bacterial Infections / Q000188:drug therapy* / Q000378:metabolism / Q000382:microbiology; D001646:Bile / Q000378:metabolism; D002439:Cefotaxime / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology / Q000627:therapeutic use; D002443:Ceftriaxone; D003106:Colon / Q000382:microbiology*; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000188:drug therapy / Q000382:microbiology; D018805:Sepsis / Q000188:drug therapy / Q000382:microbiology; D013210:Staphylococcus / Q000187:drug effects; D013291:Streptococcus / Q000187:drug effects; D015003:Yeasts / Q000187:drug effects* / Q000254:growth & development
D002443:Ceftriaxone; D002439:Cefotaxime