Effect of bromhexine on the pharmacokinetic of tilmicosin in broiler chickens

Abstract

Concurrent administration of drugs may alter their pharmacokinetic parameters, so; investigation to what extent bromhexine hydrochloride affects the pharmacokinetic behavior of tilmicosinwas our aim of this work. Ten broiler chickens were classified intotwo groups as follow, the firstone (tilmicosin group) was given single oral dose of tilmicosin(20 mg/kg.b.wt.) while the 2nd(pre-treated group) wasgiven single oral dose of bromhexinehydrochloride (1 mg/kg.b.wt.) followed by single oral dose oftilmicosin(20 mg/kg.b.wt.) one hour later. The serum concentration of tilmicosin was measured usingHigh Pressure Liquid Chromatography (HPLC) method. The results revealed that the mean serum concentrations of tilmicosinwere significantly lower in pre-treated group when compared with tilmicosinalone group at the corresponding time intervals. Pharmacokinetic parameters were significantly differed(p<0.001) between bothgroups.The maximum serum concentration were (Cmax0.70±0.02, 0.81±0.04µg/ml), achieved at Tmaxof (tmax0.89±0.16,and 2.10±0.06h),absorption half-life (t0.5ab) of 0.16±0.08,and 0.37±0.01hour, area under curve (AUC) of 12.96±0.42and 16.73±0.42µg.h/ml)in tilmicosinbromhexineand tilmicosinalonegroups respectively. In conclusion,based on the obtained pharmacokinetic parameters, these findings showed that bromhexine accelerates the tilmicosin penetration into body tissues, achieving higher and faster concentrations than when given tilmicosin alone.