Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Hyperthyroidism ?
    ### Response:
    Hyperthyroidism has several causes, including
                
- Graves disease  - thyroid nodules  - thyroiditis, or inflammation of the thyroid  - consuming too much iodine  - overmedicating with synthetic thyroid hormone, which is used to treat underactive thyroid

    