1. Patients who are pregnant or breastfeeding are not allowed to take 131 iodine treatment; patients with high fever, frequent diarrhea, vomiting and heart rate over 140 beats per minute should not take 131 iodine treatment immediately. 2. Fasting before taking 131 iodine treatment and fasting for 2 hours after taking 131 iodine treatment, please drink more water on the same day. 3. Take rest after 131 iodine treatment to prevent infection and avoid mental stimulation. For those who suffer from motion sickness, it is best to leave the city and go home only the next day. 4. Avoid heavy physical labor for a short period of time (one month) after taking 131 iodine, and engage in light physical work. 5. Avoid close contact with infants and children for at least one week after taking 131 iodine. 6. Avoid iodine for one month. Avoid eating iodine-containing foods (kelp, seaweed, seafood, etc.) or some herbs (such as summer mushroom grass, aromatic herbs, etc.), and avoid stimulating foods (chili, wine, etc.) for one month after taking 131 iodine. 7. Women should not get pregnant within six months after taking 131 iodine treatment, and men should take contraceptive measures within six months. 8. Some patients may experience pain in the thyroid gland or skin allergy (itchy skin, rash) for a short period of time (1 to 2 weeks) after taking 131 iodine, which usually disappears gradually after 1 to 2 weeks. 9.Some patients may experience a brief aggravation of the disease within 1-4 weeks after taking 131 iodine treatment, so please take adjuvant medication at the same time. However, if symptoms such as high fever (>39°C), frequent vomiting and diarrhea, and particularly fast heart rate (>140 beats/min) occur, please go to the nearest local hospital immediately. 10.After one dose of medication, the effect will be obvious in 4-6 weeks, and the symptoms will basically disappear or be cured in 2-3 months; a few patients may have symptoms of hypothyroidism. In order to better understand the condition after treatment, go to the hospital for review and consultation after 3 months.