Thyroid nodular enlargement and tenderness may be caused by subacute thyroiditis, thyroid cyst intracystic hemorrhage, thyroid cancer, etc. It can be treated with aspirin, prednisone and other medications, surgical treatment or radiotherapy. 1. Subacute thyroiditis: Subacute thyroiditis can cause nodular enlargement of the thyroid gland and tenderness, which can be treated with aspirin, ibuprofen and other non-steroidal anti-inflammatory drugs, or prednisone if the symptoms are severe. 2. Intracapsular hemorrhage of thyroid cysts: Intracapsular hemorrhage of thyroid cysts increases the tension of the cyst’s pericapsular membrane and exerts pressure on the surrounding tissues, resulting in pain and enlargement, which can be treated by sclerotherapy, fine-needle aspiration or surgical excision of the cyst. 3. Thyroid cancer: rapid growth of thyroid cancer invades the skin, mucous membrane and peripheral nerves and causes pain, which can be treated by surgery to remove the thyroid gland, radiotherapy or chemotherapy and other comprehensive treatment measures. Patients with painful thyroid nodules should go to the hospital in time to improve the examination and give targeted treatment measures after clarifying the cause of the disease.