Radiopharmaceuticals are drugs containing radionuclides used for clinical diagnosis and treatment. With the progress of nuclear technology, nuclear medicine as a new fringe discipline has been rapidly developed, belonging to the field of nuclear medicine, the use of radiopharmaceuticals has increased accordingly. So, are radiopharmaceuticals harmful to human body? Is it safe to use? This is not only the patient is not clear, even many doctors do not know. As a result, the hazards of radiopharmaceuticals have been overstated in many cases, causing unnecessary psychological burdens for users. In fact, the use of radiopharmaceuticals is very safe, 131 iodine treatment of hyperthyroidism will not bring radiation damage to people, and is not scary. After entering the human body, radioactive 131 iodine is absorbed by the gastrointestinal tract, and when it flows through the thyroid gland with the blood circulation, it is taken up by the thyroid gland and stays in the gland cells. Iodine 131 releases beta rays, which are concentrated in the gland, and through the biological effect of radiation, thyroid cells are damaged and destroyed, and some cells are necrotic and dissolved, so as to achieve the therapeutic purpose. Since iodine only concentrates in the thyroid gland after entering the human body, and the total amount of iodine in the thyroid gland accounts for 90% of the iodine in the whole body, similarly, radioactive 131 iodine only gathers in the thyroid gland, and the iodine that is not absorbed by the thyroid gland is soon discharged by the urine and feces, thus it will not cause any damage to the other organs, and it only produces a small amount of radiation to the whole body in the process of the blood circulation from the gastrointestinal tract to the thyroid gland. According to experimental research, when the thyroid gland absorbs 131 iodine at a rate of 55% and is given 131 iodine according to the therapeutic dose, the absorbed dose of the thyroid gland to the rays is 15,000 times of that of the kidney, 18,000 times of that of the liver, 0.7 million times of that of the bone marrow, 19,000 times of that of the ovary, and 30,000 times of that of the testes; and if the rate of absorbing 131 iodine is even higher, then the absorbed dose to the above mentioned organs is even smaller, and is much lower than the limit value of the radiation protection dose. According to the special investigation, the incidence of thyroid cancer and leukemia after 131 iodine treatment for hyperthyroidism is not significantly different from that of the general population. Since 1942, when the world first used 131 iodine to treat hyperthyroidism, one million cases have been treated abroad and 100,000 cases have been treated in China. In the past, minors with hyperthyroidism were afraid to be treated with 131 iodine, but now the indications for 131 iodine treatment are gradually expanding, and children with hyperthyroidism are also treated with high-dose 131 iodine treatment in foreign countries. In recent years, our hospital has taken the lead in carrying out 131 iodine therapy for adolescent hyperthyroidism patients in China, and achieved obvious curative effect, focusing on the accuracy and individualization of the dose, so that the incidence rate of hypothyroidism is less than 5%, with a high benefit-cost ratio. The picture below shows two cases of adolescent hyperthyroidism, both long-term drug ineffective, eyes have been obviously protruding, if you do not tighten the control of the condition of the protruding eyes may also develop, one of the female patient is only 10 years old. Just as any drug has side effects, 131 iodine therapy for hyperthyroidism also has deficiencies, which are only focused on radiation damage to the thyroid gland, i.e., hypothyroidism, which is the main obstacle to be overcome by 131 iodine therapy, while radiation damage to other organs is seldom taken into consideration, because it is rare in practice and theoretically impossible. In conclusion, the use of radiopharmaceuticals is safe, and 131 iodine therapy for hyperthyroidism is a popular treatment method because of its precise efficacy, high cure rate, safety, reliability, simplicity and ease of use. It is important to note that radioactive drugs cannot be purchased at general pharmacies, and treatment can only be done at the nuclear medicine department of a hospital. Regardless of the treatment method for hyperthyroidism, patients should go to regular hospitals, and should not blindly follow advertisements or gullibly believe in the peddlers and doctors, so as to avoid delaying the treatment.