Use of radical catcher and/or inactivating substance against non-radical active oxygen, to prevent or suppress changing color of human hair into white

PURPOSE: To provide a substance which can inactivate radicals and/or nonracial active oxygen so as to inhibit or suppress changing color of human hair into white. CONSTITUTION: At least one kind of a radical catcher which is physiologically allowed, and/or at least one kind of substance which is physiologically allowed and can inactivate nonracial active oxygen for a compounded drug for treating hair and scalp in order to prevent or inhibit changing color of human hair into white. As for the radical catcher or the substance to in activate nonracial active oxygen, for example, antioxidant or metalproteid can be used.