Stopping the drug before taking iodine may cause symptoms such as trembling hands, weakness, and in severe cases, panic, so it is recommended to follow the doctor’s advice for treatment. Before iodine 131 treatment, patients are generally advised to stop taking methimazole for 2-7d and propylthiouracil for 2-4 weeks, while special cases (such as severe hypermetabolic symptoms) require targeted treatment. Patients are advised to abstain from eating seaweed, nori, deep-sea fish oil, iodine-containing multivitamins for about 2 weeks. Avoid high iodine level in the body, resulting in the process of taking iodine 131 at a later stage, radioactive iodine and food iodine competition, poor absorption effect affecting the therapeutic effect. After stopping the medication, symptoms of hyperthyroidism will reappear, such as trembling hands, hyper appetite, excessive sweating and palpitations. These symptoms are temporary and can recover slowly after taking iodine 131. Some patients may have panic attacks at severe points, which need to be treated under the guidance of a doctor. During the withdrawal period, patients need to do thyroid ultrasound and other examinations under the guidance of the doctor to monitor the condition, and at the same time maintain a good state of mind to cooperate with the treatment.