The present study was designed to investigate the effect of efflux protein inhibitors glycyrrhizic acid and glycyrrhetenic acid on pharmacodynamics and pharmacokinetics of enrofloxacin in chicken. The pharmacokinetic study was carried out in broiler chicken by randomly dividing eighteen birds into three groups of six each. Birds with enrofloxacin @10 mg.kg-1body weight orally served as control. Treatment groups received glycyrrhizic acid and glycyrrhetenic acid orally along with enrofloxacin. Blood samples were collected at predetermined time intervals upto 48 h and plasma concentrations of enrofloxacin were determined by HPLC with UV detection at 277 nm. The pharmacodynamic study was carried out by determining the MIC of enrofloxacin against E. coli ATCC25922 as per the CLSI guidelines. Cmax and AUC of enrofloxacin was enhanced in treatment groups. The MIC of enrofloxacin was improved in the presence of phytochemicals. In conclusion, glycyrrhizic acid and glycyrrhetenic acid enhanced the antibacterial activity of enrofloxacin.