Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Cushing's syndrome ?
    ### Response:
    What causes Cushing's syndrome? Cushing's syndrome is caused by long-term exposure of the body's tissues to cortisol, a hormone that is naturally produced by the adrenal gland. Exposure to too much cortisol can result from long-term use of corticosteriod medications used to treat inflammatory illnesses.
    