Effect of meloxicam co-treatment on pharmacokinetics of ceftriaxone in sheep

In the present study, effect of meloxicam co-treatment on pharmacokinetic parameters of ceftriaxone (CTRX) was investigated in sheep. Plasma CTRX concentration in meloxicam co-treated animals (G-II) remained higher than in animals given CTRX alone (G-I). Pharmacokinetic analysis revealed that regression coefficient for distribution phase (α), half-life of distribution phase (t1/2α), rate of drug diffusion from peripheral to central compartment (K₁₂), elimination rate constant from central compartment (K_el) and periphera/central compartment drug concentration ratio (P/C) did not differ significantly between the two groups. In G-II, volume of distribution in area under curve (Vd_area)and total body clearance (Cl_B) were lower, while area under the plasma concentration (AUC) curve was higher than G-I. Comparatively higher value of P/C ratio suggested higher tissue CTRX concentration in G-II. It can be concluded that meloxicam co-treatment enhances the plasma concentration as well as tissue distribution of ceftriaxone.