Farmakokinetika ceftriaksona u teladi

The pharmacokinetics of ceftriaxone was determined after a single intravenous and intramuscular administration at the dose rate of 10 mg/kg in crossbred cow calves. The drug concentration in plasma was quantified through High Performance Liquid Chromatography with UV detection. Following intravenous administration the drug was rapidly distributed (t1/2α: 0.13 ± 0.01 h; Vd(area); 0.44 ± 0.07 L/kg) and eliminated (t1/2β: 1.58 ± 0.06 h) from the body with a clearance rate of 3.15 ± 0.41 mL/min/kg. Following intramuscular administration, the peak plasma drug concentration (Cmax) was 15.34 ± 2.39 μg/mL at 0.25 hours (Tmax) suggesting very rapid absorption. The drug was extensively distributed (Vd(area): 1.16 ± 0.15 L/kg) and slowly eliminated (t1/2β: 5.02 ± 0.51 hours; Cl(B): 2.71 ± 0.29 mL/min/kg) following intramuscular administration. The absolute bioavailability of ceftriaxone was 47.0 ± 5.0% following intramuscular injection. However, it can be used at a dosage of 10 mg/kg intramuscularly, repeated at twelve-hourly intervals, for the treatment of susceptible bacteria infections in calves.Farmakokinetika ceftriaksona određivana je u križane teladi nakon njegove jednokratne intravenske i intramuskularne primjene u dozi od 10 mg/kg. Koncentracija lijeka u plazmi određivana je tekućinskom kromatografifi jom visokog učinka s UV zrakama. Raspodjela lijeka bila je brza nakon intravenske primjene (t1/2α: 0,13 ± 0,01 h; Vd(area): 0,44 ± 0,07 L/kg), a izlučivanje (t1/2β: 1,58 ± 0,06 h) iz tijela s klirensom od 3,15 ± 0,41 mL/min/kg. Nakon intramuskularne primjene vršna koncentracija u plazmi iznosila je (Cmax) 15,34 ± 2,39 μg/mL tijekom 0,25 sati (Tmax) što upućuje na vrlo brzu apsorpciju. Raspodjela lijeka bila je izrazito dobra (Vd(area) 1,16 ± 0,15 L/kg), a izlučivanje sporo (t1/2β: 5,02 ± 0,51 sati; Cl(B): 2,71 ± 0,29 mL/min/kg) nakon intramuskularne primjene. Apsolutna biološka raspoloživost nakon intramuskularne primjene ceftriaksona iznosila je 47,0 ± 5,0%. Međutim, on se može rabiti u dozi od 10 mg/kg i.m. te ponavljati u razmacima od 12 sati radi liječenja bakterijskih zaraza u teladi