PURPOSE: To obtain a treating agent for diseases resulting from male sex hormone excess, such as prostatomegaly, prostatic tumor, testicular hypertrophy and testicular tumor, comprising cyclodextrin or a derivative thereof as an active ingredient.

CONSTITUTION: A treating agent comprising cyclodextrin or a derivative thereof such as etherified cyclodextrin as an active ingredient and useful for preventing, treating and alleviating all diseases based on excessive secretion of male sex hormones, such as testicular hypertrophy, testicular cancer, prostatic hypertrophy (prostatomegaly, prostatic cancer or prostatic carcinoma), acquired or congenital adremogenital syndrome. A dose of the active ingredient is generally 1μg/kg-500 mg/kg, preferably 10μg/kg-200mg/kg and is administered once-four times daily or as a durable preparation.