Abstract:Objective: The aim of this study is to develop a simple and rapid HPLC method and investigate the effect of glycyrrhizin on pharmacokinetic fate of paeoniflorin after intravenous administration. Method: Paeoniflorin and glycyrrhizin was administrated to rat via vena caudalis, and paeoniflorin in rat plasm was determined by RP HPLC method and internal standard method. All data were subsequently processed by the pharmacokinetic Software WinNonLin. The non compartmental pharmacokinetic parameters of area under the plasma concentration time curve (AUC/min·mg·L-1), clearance (CL/mL·min-1·kg-1) and volume of distribution (Vd/mL·kg-1) were calculated based on moment methods. Result: The values of AUC, Vd and CL was16681±2694, 39433±2952, 1840±312 in control group, respectively; however, the values of AUC, Vd, CL was 23544±4648, 26663±4843 and 1316±259 in experimental group. Conclusion: Glycyrrhizin significantly influenced the pharmacokinetic fate of paeoniflorin, increasing the value of AUC and decreasing CL and Vd.