SMALL RUMINANT RESEARCH, vol.169, pp.108-112, 2018 (SCI-Expanded)
The objective of this study was to evaluate the pharmacokinetics of CTX following intravenous administration of ascending doses in sheep. In this study, six clinically healthy Akkaraman sheep (2.4 +/- 0.4 years and 50 +/- 3 kg of body weight) were used. CTX was administered intravenously to each sheep at 20, 40, and 80 mg/kg doses in a crossover design with a 15-day washout period. Plasma concentrations of CTX were measured using the high-performance liquid chromatography-UV method. Pharmacokinetic parameters were calculated by non-compartmental analysis. CTX was well tolerated following administration at 20, 40, and 80 mg/kg doses. The elimination half-life following administration of 40 and 80 mg/kg doses were significantly longer than that of 20 mg/kg dose (P < 0.05). The volume of distribution at steady state was similar among the groups (P > 0.05). When compared to 20 mg/kg, dose-normalized AUC(0-infinity) at the 80 mg/kg dose significantly increased (P < 0.05). The relation between dose and AUC(0-infinity) was linear. Our study showed that CTX can be used at 12-h intervals for 20, 40, and 80 mg/kg doses to maintain T > minimum inhibitory concentration (MIC) of > 40% for the treatment of infections caused by bacteria with MIC values <= 2, <= 4, and <= 16 mu g/mL, respectively. This information may be helpful in adjusting the dosage regimen, but there is a need for future work.