Sophora flavescens is a species of plant in the genus ''Sophora''. Ku shen or kushenin is a typical traditional Chinese medicine that is found in this plant. It is commonly used for the treatment of viral hepatitis, cancer, viral myocarditis, gastrointestinal hemorrhage and skin diseases .
Its roots contain quinolizidine alkaloids, includying matrine and its oxide, that interfere TNF-alpha and IL-6, suggesting that oxymatrine may inhibit the expression of the above pro-inflammatory cytokines. Matrine also inhibited expression of Substance P and NK-1R in a human model of skin inflammation, as well as acting as an agonist at mu and kappa opioid receptors.