Hyperthyroidism, or hyperthyroidism for short, is a relatively common endocrine disease that is a clinical syndrome caused by excessive secretion of thyroid hormones due to a variety of etiologic factors. There are many causes of hyperthyroidism, of which Gvaves disease (GD) is the most common, accounting for about 90%. Classification of the causes of hyperthyroidism Thyrotoxic hyperthyroidism Graves’ disease Multinodular goiter with hyperthyroidism Highly functional autonomous thyroid adenomas (single or multiple, Plummer’s disease) Multiple autoimmune endocrine syndromes with hyperthyroidism Thyroid carcinoma (follicular cell carcinoma) Hyperthyroidism of the newborn Hyperthyroidism Iodine hyperthyroidism (Jod-Basedow’s disease) Hyperthyroidism due to mutations in TSH receptor genes Hyperthyroidism of the pituitary gland (TSH) Pituitary hyperthyroidism (TSH) Hyperthyroidism due to pituitary TSH tumor or TSH cell hyperplasia Selective pituitary thyroid hormone resistance syndrome Tumorigenic endocrine syndrome and/or HCG-associated hyperthyroidism Malignant neoplasms (lung, gastric, intestinal, pancreatic, chorionic villus, etc.) with hyperthyroidism (secretion of TSH or TSH analogs) HCG-associated hyperthyroidism (chorionic carcinoma, chorionic villous carcinoma, gravidarians, and multiple gestations, etc.) Ovarian goiter with hyperthyroidism Physically derived hyperthyroidism Temporary hyperthyroidism Subacute thyroiditis (de Quervain’s thyroiditis) Postpartum thyroiditis (PPT) Painless thyroiditis Radiation thyroiditis Drug-induced thyroiditis (e.g., interferon alpha, interleukin-2 for hepatitis, oncologic diseases, etc.) Chronic lymphocytic thyroiditis (Hashimoto’s thyroiditis, HT)