The medication taken after thyroidectomy is levothyroxine sodium tablets. In clinical practice, thyroidectomy is performed for benign thyroid diseases and malignant thyroid diseases. In benign thyroid diseases, such as nodular goiter, thyroid adenoma, and thyroid cystadenoma, thyroxine levels usually do not decrease after unilateral thyroidectomy, and no supplemental medication is needed. For malignant thyroid tumors, i.e. thyroid cancer, radical thyroid cancer resection requires total resection of the affected side plus total resection of the isthmus, plus subtotal resection of the contralateral side. After the surgery, there will be a decrease in T3, T4, free T3 and T4, and an increase in TSH, which will require supplementation with an appropriate amount of levothyroxine sodium tablets to suppress the tumor.