PROBLEM TO BE SOLVED: To provide a tetrahydrobiopterin production promoter.SOLUTION: The tetrahydrobiopterin production promoter comprises as active ingredient a chlorogenic acid compound or a pharmaceutically acceptable salt thereof.COPYRIGHT: (C)2008,JPO&INPIT【課題】テトラヒドロビオプテリン産生促進剤の提供。【解決手段】クロロゲン酸類又はその薬学的に許容される塩を有効成分とするテトラヒドロビオプテリン産生促進剤。【選択図】なし