Slightly enlarged thyroid gland should pay attention to the examination of thyroid function, because the level of thyroid hormone reflects whether the thyroid gland is in a slightly enlarged state, whether there is a state of hyperfunction or hypothyroidism, which is crucial for judging whether the goiter needs to be treated or not. If the thyroid hormone level is completely normal in patients with goiter, no clinical treatment is needed and patients do not need to worry too much. If the thyroid hormone level is significantly elevated and the thyrotropin level is low, it belongs to the state of primary hyperthyroidism, and the goiter is related to hyperthyroidism, which needs to be treated with antithyroid drugs. If the check of thyroid hormone level suggests low and thyrotropin level gets significantly elevated, it is consistent with the manifestation of primary hypothyroidism, goiter is caused by hypothyroidism, after the patient takes oral eugenol replacement therapy, the thyroid function will return to normal, and the condition of goiter will be improved.