Calcium supplements are generally not needed after thyroidectomy; if the parathyroid glands are mistakenly injured during surgery, calcium supplements are needed. For patients with hyperthyroidism, if the operation goes well and the parathyroid glands are not damaged during the operation, there is no need to take calcium supplements after the operation; if the parathyroid glands are mistakenly injured during the operation and all of them are mistakenly cut, it will cause a decrease in the concentration of calcium in the blood, and calcium supplements will be needed after the operation. Mistakenly cutting the parathyroid glands will cause hypoparathyroidism, and the corresponding symptoms, such as pinprick sensation and numbness of the face and lips, as well as persistent spasms of the hands and feet, will appear 1~3 days after the operation, which can occur several times a day and can be fatal in severe cases. Calcium supplements are needed after the seizures of the hands and feet occur. Calcium gluconate or lactate is given orally for mild cases, and vitamin D3 is added for more severe cases, as well as oral dihydrotachysterol. If symptoms such as twitching of the hands and feet occur after thyroidectomy, seek medical attention.