Resumo

PORTA, N et al. Comparative pharmacokinetics of a long-acting amoxicillin formulation following its subcutaneous and intramuscular administration to dogs. InVet [online]. 2015, vol.17, n.1, pp.17-23. ISSN 1668-3498.

The influence of the route of administration on the amoxicillin pharmacokinetics in dogs was investigated following the subcutaneous or intramuscular administration of 15 mg/kg amoxicillin formulated as a long-acting aqueous suspension. Serial blood samples were collected at predetermined times. Pharmacokinetic parameters were calculated from the disposition curves for both routes for each animal. Significant differences were observed for the parameters area under the curve (73.8 ± 13.1 mg.h/ml versus 88.3 ± 17.0 mg.h/ml) and mean residence time (6.9 ± 2.8 h versus 10.3 ± 6.1 h) following the intramuscular and subcutaneous injections, respectively. The subcutaneous administration exhibited higher depot effect than the intramuscular administration. No significant differences were observed for the time above the minimun inhibitory concentrations for bacteria of low (4 mg/ml) and high (0.250 mg/ml) amoxicillin sensitivity. Our data suggest that the tested formulation can be used with a prolonged interval of 48 h for high sensitivity bacteria, and that both routes of administration provide similar kinetic profiles and thus, similar clinical outcomes.

Palavras-chave : Pharmacokinetics; Antibiotics; Betalactams; Aminopenicillins; Dogs.