Faculty of Veterinary Medicine University of Zagreb
Abstract
Disposition and urinary excretion of levofloxacin following a single intravenous administration of 4 mg/kg body mass were investigated in six febrile crossbred calves. The drug levels in plasma and urine were estimated by microbiological assay. Levofloxacin was rapidly distributed from the blood to the tissue compartment, as evidenced by the high values of the distribution coefficient (9.93 ± 0.73 h -1). The high AUC (11.5 ± 0.95 µg/mL/h) indicated good antibacterial activity of levofloxacin in calves. The elimination half-life, volume of distribution and total body clearance were 2.22 ± 0.07 h, 1.18 ± 0.15 L/kg and 0.36 ± 0.03 L/kg/h, respectively. About 37.7 per cent of the administered dose of levofloxacin was eliminated in urine within 24 h. An appropriate intravenous dosage regimen for levofloxacin would be 5.0 mg/kg, repeated at 12 h intervals for the treatment of bacterial infections, manifested with fever in calves.Istražena je raspodjela levofloksacina i njegovo izlučivanje mokraćom nakon jednokratne intravenske primjene u dozi od 4 mg/kg tjelesne mase u šestero febrilne križane teladi. Razine lijeka u plazmi i mokraći bile su procijenjene na osnovi mikrobiološkog postupka. Levofloksacin se brzo proširio iz krvi u tkiva što je vidljivo po visokim vrijednostima koeficijenta raspodjele (9,93 ± 0,73 h). Visoki AUC (površina ispod krivulje) (11,5 ± 0,95 µg/mL/sat) upućuje na dobro antibakterijsko djelovanje levofloksacina u teladi. Poluvrijeme eliminacije iznosilo je 2,22 ± 0,07 sati, volumen raspodjele 1,18 ± 0,15 L/kg, a ukupni klirens 0,36 ± 0,03 L/kg/sat. Oko 37,7% primijenjene doze levofloksacina bilo je tijekom 24 sata izlučeno putem mokraće. Kod bakterijskih zaraza što se očituju vrućicom levofloksacin treba primijeniti u dozi od 5,0 mg/kg u razmaku od 12 sati
