Pharmacokinetics of immediate and sustained reléase cephalexin administered by different routes to llamas (Lama Glama).

PRADOS, ANA PAULA; BRAMUGLIA, GUILLERMO; KREIL, VERÓNICA; TARRAGONA, LISA; REBUELTO, MARCELA; AMBROS, LUIS; AGUSTINA MONFRINOTTI

Advances in Pharmacological Sciences

Hindawi

Año: 2016

1687-6334

We investigate the pharmacokinetics of two different cephalexin formulations administered to llamas by the intravenous (IV),intramuscular (IM), and subcutaneous (SC) routes, the minimum inhibitory concentration (MIC) of cephalexin against someEscherichia coli and staphylococci isolated from llamas, and we apply the PK/PD modelling approach, so that effective dosagerecommendations for this species could be made. Six llamas received immediate (10mg/kg, IV, IM, and SC) and sustained (8mg/kgIM, SC) release cephalexin. Pharmacokinetic parameters were calculated by noncompartmental approach. Immediate release SCadministration produced a significantly longer elimination half-life as compared with the IV and IM administration (1.3 ± 0.2versus 0.6 ± 0.1 and 0.6 ± 0.1 h, resp.) and higher mean absorption time as compared with the IM administration (1.7 ± 0.5 versus0.6 ± 0.4 h). Absolute bioavailability was in the range of 72?89% for both formulations and routes of administration. CephalexinMIC90 values against staphylococci and E. coli were 1.0 and 8.0 𝜇g/mL, respectively. Our results show that the immediate releaseformulation (10mg/kg) would be effective for treating staphylococcal infections administered every 8 h (IM) or 12 h (SC), whereasthe sustained release formulation (8mg/kg) would require the IM or SC administration every 12 or 24 h, respectively.