A Kampo medicine, Boi-ogi-to (Fang-ji-huang-qi-tang), is one of the traditional prescriptions and consists of Stephania tetrandra Radix (Stephania), Astragali Radix (Astragali),

been used clinically in the treatment of arthritis and edema in China and Japan. Boi-ogi-to is also suggested to improve in-directly an abnormal metabolism of glucose and lipid in dia-betic patients with obesity.1) We have previously reported that Boi-ogi-to increases blood insulin level and decreases blood glucose level in streptozotocin (STZ)-diabetic mice. The anti-hyperglycemic action of Boi-ogi-to depends on the ac-tion of Stephania but not Sinomeni Caulis ET Rhizoma in the prescription.2) Astragali does not have a direct anti-hyper-glycemic effect but potentiates the actions of Stephania on blood levels of glucose and insulin.3) Stephania contains many bis-benzylisoquinoline-type compounds such as tetrandrine and fangchinoline.4,5) Tetran-drine is a principle compound and shown to be effective in experimental allergic encephalitis, airway micro vascula