The principle of treatment is that iodine 131 releases beta rays in the process of decay, and beta rays have strong ionizing radiation ability, which makes part of the thyroid follicular cell degeneration and necrosis, and reduces the synthesis and secretion of thyroid hormone, and the volume of thyroid gland is also reduced, thus achieving the purpose of treating hyperthyroidism. However, it should be noted that pregnant and lactating women are prohibited. It is recommended that patients who need to treat hyperthyroidism consult the endocrinology department of a regular hospital.