Ceclobid Mechanism of Action

Pharmacology: Pharmacokinetics: Cefaclor is well absorbed from the gastrointestinal tract but plasma concentrations are slightly lower than those achieved with Cephalexin or Cephradine. Doses of 250, 500 and 1000 mg by mouth produce peak plasma concentrations of about 6, 13, 23 µg per mL respectively at 0.5 to 1 hour. The presence of food may delay the absorption of Cefaclor, but the total amount absorbed is unchanged. A plasma half-life of 0.5 to 1 hour has been reported; it may be slightly prolonged in renal failure. About 25% is bound to plasma proteins. It is rapidly excreted by the kidneys; up to 85% of a dose appears unchanged in the urine within 8 hours, the greater part within 2 hours. High concentration of 600, 900 and 1,900 µg per mL have been reported after doses of 250, 500 and 1,000 mg respectively. Probenecid delays excretion. Cefaclor is removed by haemodialysis.
Microbiology: Cefaclor is bactericidal and has antimicrobial activity but is reported to be more active against Gram-negative bacteria including Escherichia coli, Klebsiella pneumoniae, Neisseria gonorrhea, and Proteus mirabilis especially against Haemophilus influenzae. It is active against some beta-lactamase-producing strains of H. influenzae. It may be less resistant to staphylococcal penicillinase than cephalexin or cephradine and a marked inoculum effect has been reported in vitro.