What are the causes of hyperthyroidism?

Hyperthyroidism: Graves disease is an autoimmune disease most common in young women. Other common forms are toxic nodular goiter, subacute thyroiditis, post-partum thyroiditis, and of course overreplacement with thyroid hormone. There are other, less common forms of hyperthyroidism, some of which can be subtle. Best to have this evaluated by an endocrinologist or an internist who is familiar with this.

Graves' disease: Autoimmune thyroid disease- graves' disease is the most common cause of hyperthyroidism. Other causes include inflammation of the thyroid, drug induced hyperthyroidism, hyperactive thyroid nodule or nodules, rarely pituitary tumor....