Patients with low thyroid stimulating hormone (TSH) can be treated with medication, iodine-131, and surgery if they are hyperthyroid; subacute thyroiditis and low thyroid stimulating hormone caused by chorionic gonadotropic hormone during pregnancy have a tendency to heal on their own and can be left untreated. 1. Hyperthyroidism: If triiodothyronine and thyroid hormone increase, but TSH decreases, it is considered hyperthyroidism, which can be treated by drugs, iodine-131 and surgery. Drug treatment is suitable for mild and moderate cases, and the drugs include propylthiouracil and methimazole, etc. Surgical treatment is suitable for people with significant enlargement of the thyroid gland and symptoms of compression, and iodine-131 treatment is suitable for people with enlargement of the thyroid gland of the second degree or more. 2. Subacute thyroiditis: Because viral infections can cause destruction of the thyroid gland, neck pain, fever, and palpitations and excessive sweating similar to hyperthyroidism, the examination can also be seen in the lowering of TSH. If the diagnosis of subacute thyroiditis is confirmed, the patient has a tendency to recover on his own and may not be treated. 3. In the first trimester of pregnancy, human chorionic gonadotropin-associated hyperthyroidism can occur, which is pseudo, and also has a tendency to heal itself, so it can be left untreated for the time being, but it is necessary to review the thyroid function regularly. Patients with low thyroid stimulating hormone should consult a doctor in time to identify the cause of the disease, and under the guidance of the doctor for treatment.