In the past month, several friends have been anxiously asking on the phone, “I’ve been tested for an enlarged thyroid, could it be hyperthyroidism? Should I have an operation?” I’m not sure if I need surgery. The need for knowledge about thyroid disorders is so strong for people around me alone, so I can imagine that there will be more people without doctor friends around and more anxious. Therefore, I would like to share some knowledge about hyperthyroidism and hypothyroidism with my readers. Hyperthyroidism (hyperthyroidism) and hypothyroidism (hypothyroidism) are changes in the function of the thyroid gland caused by various thyroid disorders. Under normal conditions, the thyroid gland synthesizes and secretes a certain amount of thyroid hormones to maintain the body’s function in a normal state. If for some reason the thyroid gland synthesizes and secretes excessive amounts of thyroid hormones, hyperthyroidism is the result. Conversely, if the thyroid gland synthesizes and secretes insufficient amounts of thyroid hormones for any reason, the condition is called hypothyroidism. So, how can you recognize these two diseases? I wonder if it has ever happened to you that when a colleague has an inexplicable temper tantrum or a high level of excitement, he or she will be jokingly asked: “You are not hyperthyroid, are you? This is because thyroid hormone can be commonly thought of as an “excitatory” hormone that boosts the metabolic rate. In hyperthyroidism, the level of thyroid hormone in the body is higher than normal, and the patient may experience increased food intake, more frequent stools, weight loss, feeling hot and sweaty, etc. Also, due to the increased excitability of the nervous system, the patient may become irritable and irritable. In hypothyroidism, due to the lower than normal level of thyroid hormones, the patient’s performance is the opposite of the above-mentioned hyperthyroidism, such as not thinking about eating and drinking, constipation, weight gain, feeling cold, etc. At the same time, the speech speed becomes slower and less responsive, and the patient becomes a person with no temper. In addition to the above, other manifestations of hyperthyroidism include rapid heartbeat and heart rhythm disturbances such as atrial fibrillation. In conclusion, the manifestations of the disease are always very different and individual. The most common thyroid disorders that cause hyperthyroidism include diffuse toxic goiter (also known as Graves’ disease), toxic thyroid adenoma, Hashimoto’s hyperthyroidism, and subacute thyroiditis. The most common causes of hypothyroidism include: Hashimoto’s thyroiditis, after total or subtotal thyroidectomy, and after 131I treatment for hyperthyroidism. In addition to these common causes, there are many other uncommon diseases that can also cause hyperthyroidism or hypothyroidism. So, do all goiters have hyper- or hypothyroidism? An enlarged thyroid is an abnormality in the shape of the thyroid gland, while hyperthyroidism and hypothyroidism are abnormalities in the function of the thyroid gland. If the enlarged thyroid gland does not cause changes in thyroid function, it is called “simple goiter” and does not require treatment for the time being. If it is combined with hyperthyroidism or hypothyroidism, it needs to be treated. Treatment for hyperthyroidism varies depending on the cause. Here we will discuss the treatment of Graves’ disease, which is the most common. The most common treatments for Graves’ disease include antithyroid medication, surgery, and radioactive iodine therapy. Antithyroid medications include propylthiouracil and methimazole. It is important to note that before and during treatment with medications, changes in blood count and liver function need to be tested, as both Graves’ disease and these two medications can cause a decrease in white blood cells and abnormal liver function. Surgery is indicated for moderate to severe hyperthyroidism, for those who have failed to take medication or have relapsed, for those who have a huge thyroid gland that is compressing the surrounding organs and for those who have a nodular goiter with hyperthyroidism. Surgical treatment also has certain side effects, such as damage to the recurrent laryngeal nerve causing hoarseness, damage to the parathyroid glands causing temporary or permanent hypothyroidism or hypothyroidism, etc. Therefore, surgical indications should be carefully selected. Radioactive iodine therapy is indicated for moderate hyperthyroidism and those who are over 25 years old, those who cannot tolerate anti-thyroid medication or relapse, and those with high-functioning thyroid nodules. Complications of radioactive iodine therapy include hypothyroidism and radiation thyroiditis. In short, each treatment has advantages and disadvantages, and it is necessary to choose the most suitable treatment method by taking into account the individual patient. The treatment of hypothyroidism is relatively simple, i.e. exogenous supplementation of thyroid hormone, currently the most commonly used is levothyroxine, alias euthyroxine. Regular follow-up is required during the treatment of hypothyroidism, and the medication is adjusted to the optimal dose for the patient by testing thyroid function and patient performance. At this point, I believe you have a certain understanding of hyperthyroidism and hypothyroidism. Then, as mentioned at the beginning of this article, what should be done if an enlarged thyroid gland is detected in a physical examination? First of all, ultrasound examination of the thyroid gland should be performed to determine whether the thyroid gland is indeed enlarged (this examination can verify the result of the doctor’s touch during the physical examination), and also to determine whether the thyroid gland is diffusely enlarged or has thyroid nodules; secondly, blood sampling for thyroid function and related antibodies can clarify whether there is hyperthyroidism or hypothyroidism, and can also help identify the specific type of thyroid disease; furthermore, if there are abnormalities in the above tests, further thyroid imaging may be required. Further thyroid iodine uptake and thyroid ECT may be required if the above tests are abnormal. The incidence of thyroid disorders is increasing, but the thyroid glands are relatively isolated and close to the body surface, so the diagnosis of thyroid disorders is high and the treatment is more effective. Therefore, we hope that you will do the following: seek medical consultation as soon as possible, make a clear diagnosis, provide timely treatment, and follow up on time.