Low thyroid hormone, need to clarify the cause, often associated with primary hypothyroidism, pituitary adenoma and intracranial space-occupying lesions and other factors, treatment includes drugs (such as levothyroxine sodium tablets) and surgical treatment. 1. Primary hypothyroidism: common treatment drugs include levothyroxine sodium tablets. If there are symptoms such as palpitations, insomnia and excessive sweating after using the drug, the dosage should be reduced or suspended as prescribed by the doctor. 2. Pituitary adenoma: mostly benign tumors originated from the pituitary gland, which can lead to secondary hypothyroidism and should be removed by surgery. 3. Intracranial space-occupying lesion: it can compress the pituitary gland and lead to endocrine dysfunction, resulting in low thyroid hormone, and the primary brain tumor should be actively treated. There are many reasons for the lowering of thyroid hormone, and it is recommended that the cause and treatment be clarified under the guidance of a doctor.