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 tilmicosin was our aim of this work. Ten broiler chickens were classified into two groups as follow, the first one (tilmicosin group) was given single oral dose of tilmicosin (20 mg/kg.b.wt.) while the 2nd (pre-treated group) was given single oral dose of bromhexine hydrochloride (1 mg/kg.b.wt.) followed by single oral dose of tilmicosin (20 mg/kg.b.wt.) one hour later. The serum concentration of tilmicosin was measured using High Pressure Liquid Chromatography (HPLC) method. The results revealed that the mean serum concentrations of tilmicosin were significantly lower in pre-treated group when compared with tilmicosin alone group at the corresponding time intervals. Pharmacokinetic parameters were significantly differed (p<0.001) between both groups. The maximum serum concentration were (Cmax0.70±0.02, 0.81±0.04µg/ml), achieved at Tmax of (tmax 0.89±0.16, and 2.10±0.06h), absorption half-life (t0.5ab) of 0.16±0.08, and 0.37±0.01 hour, area under curve (AUC) of 12.96±0.42 and 16.73±0.42µg.h/ml) in tilmicosin-bromhexine and tilmicosin alone groups 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.