Objective: To study the effect of Glycyrrhiza uralensis on metabolism

distribution and excretion of triptonide in rat and disclose the attenuation mechanism of G. uralensis on triptonide in vivo. Method: The SD rats were divided into single and combined administration groups. The combined group was injected with triptonide after orally treated with extracts of Glycyrrhiza

while the single group was injected only with triptonide. The concentration of triptonide in plasma

tissue and excreta in vivo were determinated by LC-MS-MS method to compare with the difference of metabolism

distribution and excretion of triptonide under two administration models. Result: The determination methods with good precision and stability were suitable for the assay of triptonide in biological samples. The difference of metabolism

distribution and excretion of triptonide under single and combined administration models were significant. AUC and t1/2Zof triptonide under combined administration model were decreasing

while CL was increasing compared with single administration model. The concentration of triptonide in tissue under combined administration model was decreasing

while excretion of triptonide was accelerated compared with single administration model. Triptonide was mainly distributed in the lung under two administration models. Conclusion: Glycyrrhiza can decrease the concentration of triptonide in tissue and accelerate the excretion of triptonide in rats. It may be one of the attenuation mechanisms of Glycyrrhiza on triptonide.