Pharmacokinetics of meropenem after intravenous, intramuscular and subcutaneous administration to cats

ObjectivesThe aim of the study was to describe the pharmacokinetics and predicted efficacy of meropenem after intravenous (IV), intramuscular (IM) and subcutaneous (SC) administration to cats at a single dose of 10 mg/kg.MethodsFive adult healthy cats were used. Blood samples were withdrawn at predetermined times over a 12 h period. Meropenem concentrations were determined by microbiological assay. Pharmacokinetic analyses were performed with computer software. Initial estimates were determined using the residual method and refitted by non-linear regression. The time that plasma concentrations were greater than the minimum inhibitory concentration (T >MIC) was estimated by applying bibliographic MIC values and meropenem MIC breakpoint.ResultsMaximum plasma concentrations of meropenem were 101.02 µg/ml (Cp(0), IV), 27.21 µg/ml (Cmax, IM) and 15.57 µg/ml (Cmax, SC). Bioavailability was 99.69% (IM) and 96.52 % (SC). Elimination half-lives for the IV, IM and SC administration were 1.35, 2.10 and 2.26 h, respe...