1. What is hyperthyroidism and its classification? 1. Thyrotoxicosis: It is a general term for a disease in which the thyroid hormone increases due to the thyroid gland itself or various causes other than the thyroid gland, which enters the circulating blood and acts on tissues and organs throughout the body, resulting in increased excitability and hyper-metabolism of the circulatory, nervous, digestive and other systems of the body. 2. Hyperthyroidism (referred to as hyperthyroidism): refers to thyrotoxicosis caused by lesions of the thyroid gland itself. The main causes are Graves’ disease, multinodular goiter with hyperthyroidism, autonomous high-functioning adenoma of the thyroid gland and iodine hyperthyroidism. Clinical manifestations The most common type of hyperthyroidism is Grave’s disease. Its symptoms include increased heart rate, weight loss, nervousness, anxiety, anger, fatigue, and frequent stools. Treatment The treatment of hyperthyroidism mainly includes three methods: anti-thyroid medication, surgery, and 131 iodine treatment. However, antithyroid drugs can cause bone marrow suppression and liver function damage. If skin allergy, joint pain, lower white blood cell or neutrophil or platelet count, and liver function damage occur during treatment, the drugs should be stopped and other treatment methods should be chosen. In addition, pregnant women, especially in the first 3 months of pregnancy, must avoid taking methimazole to avoid fetal malformations. For those who have large nodules in their enlarged thyroid gland, especially those with “cold or cool” nodules, surgery is the best option after medication is used to control the symptoms. For moderate to severe hyperthyroidism, diffuse enlargement of the thyroid gland, poor results of anti-thyroid medication, reduced blood cells, and impaired liver function, 131 iodine therapy is the best choice after symptomatic treatment, which is effective, low risk, and low cost.