Thyrotoxicosis, also known as thyrotoxicosis, is a general term for a disease in which thyroid hormones are increased by the thyroid gland itself or by various causes other than the thyroid gland, entering the circulating blood and acting on tissues and organs throughout the body, resulting in increased excitability and hyper-metabolism of the nervous, circulatory, digestive and other systems of the body. Clinical symptoms The clinical manifestations of hyperthyroidism may be mild or severe, obvious or not. The clinical manifestations may not be the same due to the age of the patient, the duration of the disease, and the different lesions that cause abnormalities in various organs. Hyperthyroidism may be temporary or persistent. The most common of these is diffuse toxic goiter (Graves’ disease), which is the most common cause of hyperthyroidism and is the most common clinical thyroid disorder. Graves’ disease is most common between the ages of 20 and 40 years and is rare before the age of 10 years, and rarely is the “indifferent type”. The main clinical manifestations include diffuse goiter, thyrotoxicosis, infiltrative ophthalmopathy, and occasionally infiltrative skin disease. (1) Increased metabolism and sympathetic hyperexcitability (2) Goiter. (3) Ophthalmopathy (4) Most pediatric and elderly patients with post-illness clinical manifestations are not obvious. In many older patients, only a few 1-2 groups of symptoms are present, or only one system of symptoms is prominent. Some older patients have complaints of arrhythmia; others go to the hospital for examination because of significant weight loss. Others complain of poor appetite and reduced eating; or have tremors of the limbs as the chief complaint. Very few elderly patients show physical weakness, fatigue, lethargy, indifference and depression, which is called “indifferent hyperthyroidism”. Some children do not lose weight after developing hyperthyroidism. In some patients, the thyroid gland is not enlarged, or it is asymmetrically enlarged. Other patients have thinning, brittle or detached nails. Graves’ disease may be associated with congenital dyskeratosis and deafness, but these are rare. The etiology of Graves’ disease is not well understood, but patients have familial qualities, with about 15% of patients’ relatives having the same disease and about 50% of their family members reacting positively for antithyroid antibodies. Many studies consider Graves’ disease to be an autoimmune disease (AITD).