Low blood pressure may occur after total thyroidectomy without thyroid hormone replacement therapy. After total thyroidectomy, hypothyroidism will occur, and the body’s basal metabolic rate and sympathetic excitability will decrease, which may lead to low blood pressure, as well as symptoms such as chills, drowsiness, weakness of limbs, memory loss, dull expression, slow reaction, menstrual disorders, and slow heart rate. After total thyroidectomy, thyroxine tablets need to be taken for life, and regular checkups are required to monitor the level of thyroxine and adjust the dosage of the medication. If the blood pressure returns to normal after normalization of the thyroid hormone, it suggests that total thyroidectomy is associated with low blood pressure. If low blood pressure occurs after total thyroidectomy, it is recommended to consult a doctor to clarify the situation.