1) Patients with newly diagnosed Graves' disease
2) Serum FT4 value more than 5.0 ng/dl
3) Written informed consent from the patients' parents or legal guardians.
4) Age from 10 years old to under 16 years old
1) Patients with thyrotoxic crisis
2) Patients who receive pharmacotherapy for diabetes, hepatic and renal disease
3) Medical history of Graves' disease. Patients who have already used cholesterol absorption inhibitor.
4) Use of coumarin anticoagulants, digitalis, and bile acids preparations
5) Patients with complete obstruction of the biliary tract
6) Patients with intestinal obstruction
7) Judged inappropriate for this study by the physicians.
Reduction rate of levels of free T3 and free T4
The normalization rate of levels of free T4 and free T3 at the 8, 12, and 24 weeks treatment
Changes of levels of TRAb, Total cholesterol, CPK, total bile acid and 25 hydroxy vitamin D