Causes of hyperthyroidism?

*Grave's disease, which is an autoimmune disorder in which the immune system attacks your thyroid which results in the thyroid making too much hormone. This is the most common cause of hyperthyroidism *Thyroid nodules, which are basically growths (normally benign) on the thyroid. They nodules may become overactive and in turn produce too much thyroid hormone. *Thyroiditis, is as the name suggests inflammation of the thyroid. It causes stored thyroid hormone to leak out of the thyroid gland. *Too much iodine. Iodine is found in some medicines, cough syrups, seaweed and seaweed-based supplements. *Medication induced hyperthyroidism can occur when people who take thyroid hormone medicine for hypothyroidism take too much of it perhaps due to not having the correct blood tests .