Hyperthyroidism and Hashimoto’s hypothyroidism are not more serious, they are two diseases, it is recommended to follow the doctor’s advice and active treatment. Hyperthyroidism is a hypermetabolic condition caused by increased secretion of thyroid hormones. Treatment for hyperthyroidism includes antithyroid medication, radioactive iodine therapy, and surgery, and many patients can return to normal thyroid function after effective antithyroid treatment. Hashimoto’s hypothyroidism is the result of autoimmune-related thyroid antibodies destroying the thyroid gland, leading to a decrease in thyroid hormone production causing low metabolic symptoms. Hashimoto’s hypothyroidism requires replacement therapy with levothyroxine sodium tablets, which is generally incurable and requires lifelong treatment. Levothyroxine sodium tablets are generally safe and do not have many side effects. Both hyperthyroidism and Hashimoto’s hypothyroidism should be treated in a hospital under the supervision of a doctor.