Radiopharmaceuticals are drugs containing radionuclides for clinical diagnosis and treatment. With the advancement of nuclear technology, nuclear medicine has been rapidly developed as a new edge discipline, and the use of radiopharmaceuticals belonging to the field of nuclear medicine has increased accordingly. So, are radioactive drugs harmful to human body? Is it safe to use? This is not only unclear to patients, but also to many doctors. As a result, in many cases, the harm of radiopharmaceuticals is overstated, causing unnecessary psychological burden to the users. In fact, the use of radiopharmaceuticals is very safe. 131 iodine treatment for hyperthyroidism also does not cause any radiation damage and is not terrible. When radioactive 131 iodine enters the body, it is absorbed by the gastrointestinal tract and is taken up by the thyroid gland as it flows through the bloodstream, where it remains in the gland cells. The 131 iodine releases beta radiation, which is concentrated in the gland and causes damage and destruction to the thyroid cells through the biological effect of radiation, resulting in the necrosis and dissolution of some cells. Since iodine enters the body and is concentrated only in the thyroid gland, which contains 90% of the total amount of iodine in the body, radioactive 131 iodine also accumulates only in the thyroid gland, and what is not absorbed by the thyroid gland is quickly excreted in the urine and stool, thus causing no damage to other organs. According to the experimental study, when the thyroid gland absorbs 131 iodine at a rate of 55% and 131 iodine is given at therapeutic doses, the absorbed dose of the thyroid gland is 15,000 times that of the kidney, 18,000 times that of the liver, 0.7 million times that of the bone marrow, 19,000 times that of the ovaries and 30,000 times that of the testes. According to a special survey, the incidence of thyroid cancer and leukemia after 131 iodine treatment for hyperthyroidism is not significantly different from that of the general population. Since the first treatment of hyperthyroidism with 131 iodine in the world in 1942, 1 million cases have been treated abroad and 100,000 cases have been treated in China. Nowadays, the indications for 131 iodine treatment are gradually expanding, and high-dose 131 iodine treatment is also used for children with hyperthyroidism in foreign countries. In recent years, our hospital has pioneered 131 iodine treatment for adolescent hyperthyroidism in China, and has achieved significant efficacy, focusing on accurate and individualized dosing, resulting in an incidence of hypothyroidism of less than 5%, which has a high benefit-cost ratio. In the figure below, two adolescent patients with hyperthyroidism, both of whom had been on medication for a long time, had protruding eyes and were at risk of developing protrusion if the disease was not tightened. Like any drug, 131 iodine treatment for hyperthyroidism also has its shortcomings, which are focused on radiation damage to the thyroid gland, i.e., hypothyroidism, which is the main obstacle to overcome with 131 iodine treatment, while radiation damage to other organs is rarely considered because it is rare in practice and theoretically impossible. In conclusion, the use of radiopharmaceuticals is safe, and 131 iodine treatment for hyperthyroidism is a popular treatment method because of its precise efficacy, high cure rate, safety, reliability, and simplicity. It is important to mention that radioactive drugs are not available in general pharmacies, and treatment can only be performed in the nuclear medicine department of a hospital. Patients with hyperthyroidism should go to a regular hospital regardless of the treatment method, and should not blindly follow advertisements or trust doctors and medical professionals to avoid delaying treatment.