Ciprofloxacin (CFX) and ketoprofen (KPN) are used widely in combination in veterinary interventions for bacterial infections, so in this study the effect of KPN was studied on the efficacy of CFX, by measuring its plasma concentration and pharmacokinetic parameters in 7-10 day-old chickens. The analgesic median effective dose (ED50) of KPN was determined to be 1.62 mg/kg, IM, in the chickens. The preferable analgesic dose of KPN to be used with CFX was 4 mg/kg, IM, which differs significantly from KPN 2 mg/kg, IM,. The CFX plasma concentrations alone (8 mg/kg, IM) measured at different times (0.5, 1, 2, 4 and 24 hours) were 3.31, 3.60, 3.21, 2.70 and 0.17 μg/mL while its concentration was elevated by 53, 54, 90, 107 and 418 % when coadministered with KPN (4 mg/kg, IM) to 5.05, 5.53, 6.10, 5.59 and 0.88 μg/mL in the chickens, respectively. CFX pharmacokinetic parameters, such as the area under the curve (AUC), the area under the moment curve (AUMC), mean residence time (MRT), half-life (t1/2β), Tmax, and Cmax increased when KPN was coadministered with CFX by 129, 289, 70, 49, 100 and 69 %, whereas the elimination rate constant (Kel), the volume of distribution at steady state (Vss) and clearance (Cl) decreased by 36, 34 and 58 %, respectively. It was concluded that coadministration of KPN alters the plasma concentration and the pharmacokinetic parameters of CFX, suggesting that the CFX dose can be reduced when used with KPN to achieve the desired concentration of CFX in the plasma, as an antibacterial for treatment of infected animals.
