After thyroid cancer surgery, most patients need more than 3 months to recover completely. Because most thyroid cancers are papillary or follicular cancers, radical thyroidectomy with post-operative chemotherapy and radiotherapy can cure the cancer, and the surgery is mainly performed by total thyroidectomy with isthmus resection on the affected side, subtotal resection on the opposite side, or even total thyroid resection. However, since the thyroid gland is excised to a large extent, there is inevitably a shortage of thyroxine after surgery. Therefore, after radical thyroid cancer surgery, it is usually necessary to take thyroxine for life to maintain the body’s thyroxine level in order to avoid the symptoms of hypothyroidism. It takes 2-3 months for the body to adapt to the oral thyroxine to maintain a stable level, so it usually takes more than 3 months after thyroid cancer surgery to return to normal.