The methods to lower calcitonin in medullary thyroid cancer include surgery, radiotherapy and targeted drug therapy, and the treatment needs to be carried out under the guidance of doctor. To reduce calcitonin in medullary thyroid cancer patients, the first and foremost way is to treat medullary thyroid cancer, and after diagnosis, surgery can be chosen to remove the lesion to improve the symptoms. In addition to surgical treatment, iodine 131 treatment and targeted therapy can also be used to shrink the tumor lesions, inhibit tumor proliferation and reduce calcitonin. Targeted drugs include cabozantinib, sunitinib and so on. In addition to the occurrence of hypocalcemia, intravenous calcium gluconate and other drugs to supplement calcium treatment, postoperative thyroxine is low or can not be secreted, but also need to take levothyroxine tablets treatment. Due to individual differences, the drugs need to be standardized under the guidance of a doctor, the emergence of adverse reactions to timely medical treatment, drug allergy is prohibited.