1.Iodine-131 treatment should be stopped for about 4 weeks before iodine-131 treatment. The purpose is to increase TSH in the body to enhance the uptake of iodine-131 by thyroid cancer lesions. 2. A low iodine diet (avoiding seafood and iodine-rich foods and drugs) for 2-4 weeks prior to iodine-131 treatment is also required to increase the uptake of iodine-131 by the lesion. After discharge from the hospital, the patient should avoid close contact with pregnant women and infants for a certain period of time (2-4 weeks) and continue to maintain a low iodine diet (avoid seafood and iodine-rich foods and medicines) for 2 weeks to enhance the uptake of 131I by the lesion. etc. 3. Because of the large amount of radioactivity in the patient’s body after oral administration of iodine-131, hospitalization is required for high-dose iodine-131 treatment, and isolation is usually required for 3-7 days after administration of iodine-131 before discharge from the hospital. During the isolation period, family members are not allowed to accompany the patient. 4. If there are other systemic diseases, please consult the appropriate specialist before hospitalization. Iodine-131 treatment can only be administered after the other diseases are stabilized.