Advantages: the therapeutic effect is certain; it will not lead to permanent hypothyroidism; it is convenient, economical and safer to use. Disadvantages: long course of treatment, usually takes 1~2 years, sometimes up to several years; high relapse rate after stopping the drug, resulting in treatment failure; can also be accompanied by liver function impairment and other side effects. Dosage and course of treatment Initial treatment: propylthiouracil 300~450 mg per day, or tabazole (or hyperthyroidism) 30~40 mg per day, taken orally 2~3 times, until the symptoms are relieved or the serum thyroxine returns to normal, then the dosage can be reduced. Reduction period: about every 2~4 weeks. The dosage of propylthiouracil can be reduced by 50~100 mg each time, and tabazole or hyperthyroidism can be reduced by 5~10 mg each time. After the symptoms are completely eliminated and the signs have improved significantly, the dose should be reduced to the maintenance dose. Maintenance period: propylthiouracil 50~100 mg per day, tabazole or hyperthyroidism 5~10 mg per day. Maintain this for 1~2 years, and if necessary, halve the maintenance dose before stopping the drug. Throughout the course of treatment, it is important to avoid interruptions. If there is any stress such as infection or mental factors at any stage, it is advisable to increase the dosage at any time and then decrease it after stabilization. The dosage should be reduced only when TSH is high and T3 and T4 are low, so as to improve the cure rate. Otherwise, it is easy to relapse. For the ATD treatment process appears hyperthyroidism symptom relief but goiter or synophthalmos worsened, anti-thyroid drugs can be appropriate to reduce the amount, and can be added daily levothyroxine (L-T4) 25 ~ 50 micrograms or thyroid tablets 20 ~ 60 mg, for corrective treatment. The beta-blocker propranolol (cardioplegia) 10-20 mg three times a day can be used in combination during the first 1-2 months of antithyroid drug therapy to improve palpitations, tachycardia, nervousness, tremor, and excessive sweating, but it is contraindicated in the presence of bronchial asthma, atrioventricular block, heart failure, and childbirth, and should be used with caution in insulin-dependent diabetes mellitus. Drugs such as atenolol or metoprolol can be chosen instead. Factors affecting the efficacy ① length of treatment: ② blood TRAb level of GD patients: the remission rate of those with high TRAb level at the initial treatment is only 15%, while the remission rate of those with low TRAb level is 50%, and it is very difficult for ATD to reduce TRAb to normal. This is the main reason for the poor efficacy of ATD for GD. ③Thyroid enlargement degree: the remission rate of GD for those with small thyroid is 76%, while the remission rate for those with medium or large thyroid is 50%. The GD remission rate for those with moderately enlarged thyroid gland is only 37%. Iodine intake: the remission rate of hyperthyroidism is low in areas with high iodine intake, and it is reported that the remission rate of ATD is only 13.6% after 17.6 months of treatment. ⑤ A family history of the disease, pronounced proptosis, high blood L concentration, slow decline in treatment and poor adherence to medication are also factors affecting the efficacy of ATD.