Primary hyperthyroidism is the most common of the diseases with feverishness as a symptom, and is defined as the presence of hyperfunctional symptoms along with an enlarged thyroid gland. Patients are mostly between the ages of 20 and 40. The enlargement of the gland is diffuse and symmetrical on both sides, often accompanied by protruding eyes, so it is also called “protrusive goiter”. The examination methods are as follows. 1.General indexes: mainly include blood routine, electrolytes, liver and kidney function, etc., to help judge the general condition of the body. 2.Serum thyroid hormone level check: including the determination of serum total T3 (TT3), total T4 (TT4), free T3 (FT3), free T4 (FT4), etc. At least one of these indicators is in an increased state when hyperthyroidism is present. These indicators may be very high in patients with severe hyperthyroidism. 3. Thyrotropin (TSH): TSH is secreted by the human pituitary gland and its physiological role is to promote thyroid growth and secretion of thyroid hormones. In hyperthyroidism, the secretion of TSH is suppressed and therefore the test value is low. After hyperthyroidism is controlled, TSH gradually returns to normal, but at a slower rate than thyroid hormone. In hypothyroidism, TSH is overproduced. 4. Thyroid ultrasonography and thyroid nuclear imaging: These two tests can analyze the size of the thyroid gland, blood flow abnormalities, changes in the nodules in the thyroid gland and the nature of the thyroid gland in patients with hyperthyroidism. The results of these tests are useful for treatment decisions and allow objective comparison of thyroid changes before and after treatment.