Objective: To study the effect of compatibility using glycyrrhiza and rhubarb on pharmacokinetics of rhein in rats. Method: Sprague Dawley rats were administrated with rhubarb and Dahuanggancao Decoction respectively. The rhein in plasma was measured by high performance liquid chromatography. An HPLC method was established with Zorbox SB C18 column (4.6 mm×150 mm

5 μm)

the mobile phase was methanol-water-acetic acid (77 ∶22 ∶1)

the flow rate was 1.0 mL ·min- 1 and a detection wavelength was at 428 nm. Pharmacokinetic parameters were determined from the plasma concentration-time data with the software 3P97. Result : Rhein was linear in the range of 0.1-15 mg ·L-1. The concentration-time curves of rhein fitted well into two-compartment models in rats. Significant difference was found between the two groups. There existed significant ( P<0.05) differences in AUC

Tmax

Cmax in plasma concentration of rhein between rhubarb and Dahuanggancao Decoction. Conclusion : The concentration of rhein was decrease and the hepatic injury was reduced when glycyrrhiza was compatible with rhubarb in rats.