Hyperthyroidism, or hyperthyroidism for short, is a thyrotoxicosis caused by excessive production of thyroid hormones by the thyroid glands themselves. Its causes include diffuse toxic goiter (Graves’ disease), nodular toxic goiter, and autonomic hyperfunctioning adenoma of the thyroid gland. Over 80% of patients with hyperthyroidism are caused by Graves’ disease, which is an organ-specific autoimmune disease with a significant genetic predisposition, with a risk of 11.6% in siblings and a high concordance rate in monozygotic twins. Graves’ disease has been found to be a complex polygenic disease. Environmental factors are also involved in the development of Graves’ disease, such as bacterial infections, sex hormones, and stress, all of which have an impact on the development of the disease. The main feature of Graves’ disease is the presence of specific autoantibodies in the serum against thyroid cell thyrotropin (TSH) receptors, called TSH receptor antibodies (TRAb). TRAb binds to TSH receptors and activates the adenylate cyclase signaling system, leading to thyroid cell hyperplasia and increased thyroid hormone synthesis and secretion. Therefore, although the underlying cause of hyperthyroidism is not clear, it is certain that hyperthyroidism is caused by excessive synthesis and secretion of thyroid hormones. The most common clinical condition that causes hyperthyroidism is Graves’ disease.