Abstract: The major chemical constituents of Glycyrrhiza (glycyrrhizic acid, liquiritin) and Ephedra(ephedrine and methephedrine) in the decoction of Ephedra-Glycyrrhiza preparation combination were analyzed by high performance liquid chromatography (HPLC) and gas chromatography(GC) , respectively. And the influences of different part of Ephedra-Glycyrrhiza combined decoction to the auricular swelling of mice caused by dimethylbenzene were studied. This method can sensitively detect the difference between the single decoction and combined decoction of Glycyrrhiza, Ephedra and the Ephedra-Glycyrrhiza . Comparing to the single decoction, the abundance of glycyrrhizic acid, liquiritin, ephedrine and methephedrine in the combined decoction of Ephedra-Glycyrrhiza were 13.50% , -19.38%, 14.52% and 64.0% , respectively. The anti-inflammatory ability of combined decoction for the Ephedra-Glycyrrhiza is higher than that of their single decoction.

Key words: preparation combination, HPLC-MS/MS, GC-MS, Ephedra, Glycyrrhiza