[Pharmacokinetics and metabolism of the cephalosporins].
Apart from their antimicrobial activity pattern the cephalosporins differ by their pharmacokinetics. Most cephalosporins have a plasma half life of 30 to 120 minutes. Only ceftriaxon has a half life of about 8 hours, which implicates extended dose intervals. Cephalosporins are excreted renally. Cefoperazone and ceftriaxon, however, are excreted with the bile up to 30%. Cefalotin, cefacetril and cefotaxime are metabolized to a significant degree. Only the main-metabolite of cefotaxime shows mentionable antimicrobial activity. With regard to renal insufficiency (creatinine clearance greater than 5 ml/min) dose reduction is not necessary with cefoperazone and with ceftriaxon because of hepatic excretion and with cefotaxime because of metabolism.
D001646:Bile / Q000032:analysis; D001812:Blood-Brain Barrier; D002511:Cephalosporins / Q000032:analysis / Q000378:metabolism* / Q000652:urine; D004305:Dose-Response Relationship, Drug; D006207:Half-Life; D006801:Humans; D007408:Intestinal Absorption; D007700:Kinetics; D008099:Liver / Q000378:metabolism; D011485:Protein Binding; D014018:Tissue Distribution
D002511:Cephalosporins
Pharmakokinetik und Metabolismus der Cephalosporine.