Patients with primary hyperthyroidism require long-term oral antithyroid medication because the course of medication is not sufficient and random discontinuation of medication can easily cause a relapse of hyperthyroidism. The specific indications of when anti-thyroid medication should be discontinued are the following three: First, the patient’s symptoms of hyperthyroidism should be completely controlled, with no symptoms such as fear of heat, excessive sweating or panic, and a stable weight gain with no tendency to decline. The second rule is that the thyroid hormone level should be rechecked several times and be within the normal range, at least in six months’ time. The third one, the most crucial thing is to check the level of thyroid stimulating receptor antibodies. If the level of thyroid stimulating receptor antibodies is less than 1, and the whole treatment time of hyperthyroidism reaches 1.5-2 years, you can consider stopping the medication if you meet the above three points.