Pharmacotherapeutic group: Anti-infective for systemic use: amoxicillin and enzyme inhibitor.
ATC Vet Code: QJ01CR02
Pharmacodynamic properties
Amoxicillin is a beta-lactam antibiotic and its structure contains the beta-lactam ring and thiazolidine ring common to all penicillins. Amoxicillin shows activity against susceptible Gram positive bacteria and Gram negative bacteria.
Beta-lactam antibiotics prevent the bacterial cell wall from forming by interfering with the final stage of peptidoglycan synthesis. They inhibit the activity of transpeptidase enzymes, which catalyse cross-linkage of the glycopeptide polymer units that form the cell wall. They exert a bactericidal action but cause lysis of growing cells only.
Clavulanic acid is one of the naturally occurring metabolites of the streptomycete Streptomyces clavuligerus . It has structural similarity to the penicillin nucleus, including possession of a beta-lactam ring. Clavulanic acid is a beta-lactamase inhibitor acting initially competitively but ultimately irreversibly.
Clavulanic acid will penetrate the bacterial cell wall binding to both extracellular and intracellular beta-lactamases.
Amoxicillin is susceptible to breakdown by ß-lactamases produced by some bacterial species, and therefore combination with an effective ß-lactamase inhibitor (clavulanic acid) extends the range of bacteria against which it is active to include ß-lactamase producing species.
Pharmacokinetic properties
After parenteral administration of the maximum recommended dose to cattle, the following parameters were observed: Cmax of 1.69 µg/ml, Tmax of 2.67h, AUC of 30.59 µg/ml.h and t½ of 23.19h for amoxicillin and Cmax of 0.94 µg/ml, Tmax of 1.3h, AUC of 3.123 µg/ml.h and t½ of 1.71h for clavulanic acid.
After subcutaneous administration of the maximum recommended dose to dogs, the following parameters were observed: Cmax of 8.66 µg/ml, Tmax of 1.78h and AUC of 50.98 µg/ml.h for amoxicillin