Iodine 131 can be used with family members after discharge from the hospital, but it is recommended to avoid close contact with pregnant women, infants and young children within two weeks after treatment. The half-life of iodine 131 is about 8 days. After discharge from the hospital with iodine 131 treatment, the content of iodine 131 retained in the body is relatively low, and normal communication and activities will not cause serious harm to other healthy people, so patients discharged from the hospital with iodine 131 treatment are allowed to live with their families. However, for special people at home, such as pregnant women, infants and children, close contact should be avoided within two weeks after iodine 131 treatment. It should also be noted that in the period of time after the iodine 131 treatment, you should also avoid intimate contact with other people, such as sharing tableware, kissing, coitus, etc., so as to avoid the secretion of iodine 131 from entering into other people’s bodies. Patients discharged from the hospital after iodine 131 treatment can go to the hospital if they are not sure about the precautions to be taken after discharge, and consult a professional doctor for judgment.