The thyroid is a small, butterfly-shaped gland located at the base of the neck. It manufactures hormones that control the body’s metabolism and growth such as triiodothyronine (T3) and thyroxine (T4). Several different problems can arise if the thyroid gland isn’t working as it should. Dear Doctor explores these conditions in more detail.
Hyperthyroidism refers to a thyroid that produces too much of its hormones. This can cause several unpleasant symptoms including restlessness, a racing heart, irritability, anxiety, shaking, brittle hair and nails, thin skin, muscle weakness, weight loss and increased sweating.
A blood test is a preferred method for diagnosing hyperthyroidism. The test measures the level of T4 and thyroid-stimulating hormone (TSH). High T4 levels and low TSH levels indicate an overactive thyroid gland.
Antithyroid drugs such as methimazole are prescribed to stop the gland from producing its hormones. Other treatments like large doses of radioactive iodine aim to destroy or damage the thyroid gland. Surgery can also be performed in order to remove the thyroid entirely. Medical practitioners usually prefer the first option; damaging or removing the thyroid can lead to a hormone deficiency and may require supplements to be taken on a regular basis.
Hypothyroidism is the complete opposite of hyperthyroidism. In this case, the thyroid cannot produce enough of its regular hormones. Common symptoms of the condition include dry skin, constipation, fatigue, depression, memory problems, intolerance to cold, weight gain, weakness, slowed heart rate and, in severe cases, coma. Hypothyroidism can trigger other serious medical complications such as high cholesterol and atherosclerosis (clogged arteries), leading to a higher risk of angina or heart attack.
Like hyperthyroidism, the condition is detected through a blood test. The test will track T4 and TSH levels; a high TSH reading and a low T4 reading indicate an underactive thyroid.
The main form of treatment for hypothyroidism is a prescribed course of hormone medication. It can take some time to work out the correct dosage because hormone levels can differ greatly from person
–to-person—a specialist should be able to provide guidance in this respect.
Hashimoto’s disease, also known as chronic lymphocytic thyroiditis, is the most common cause of hypothyroidism. The condition can occur at any time, although it’s most frequently seen in middle-aged women. It involves the body’s immune system mistakenly attacking the thyroid gland, impeding its ability to produce hormones. Symptoms of the disease are often subtle at first, they include fatigue, depression, enlarged thyroid, constipation, pale and puffy face, mild weight gain, irregular menstruation and dry skin.
A blood test is the most accurate way to confirm Hashimoto’s disease. Increased levels of TSH combined with low levels of T3 or T4 will help to indicate the problem. Because Hashimoto’s disease is an autoimmune disorder, the blood test will also indicate if there are any abnormal antibodies attacking the thyroid.
Hashimoto’s disease cannot be cured but its symptoms can be treated. Usually, doctors will recommend taking thyroid hormone replacement medication. In rare circumstances surgery may be deemed necessary if the swelling is uncomfortable or cancer is suspected.
Goiter is a noncancerous enlargement of the thyroid gland; its main cause is an iodine deficiency in the diet. Goiter is conversely caused by, and a symptom of, hyperthyroidism. Mild cases of goiter may not reveal any symptoms. Progressed cases may involve swelling or tightness in the neck, coughing, wheezing, difficulty swallowing and hoarseness of the voice.
A routine physical examination conducted by a doctor will identify a case of goiter. This may involve the practitioner feeling the neck or swollen gland area. An ultrasound of the thyroid can reveal swelling or nodules. A blood test is another way to monitor hormone levels and confirm a diagnosis.
While goiters aren’t usually a huge cause for concern, they can lead to more serious conditions if left untreated. If iodine deficiency is the cause, doctors may prescribe small doses of iodine to resolve the problem. Radioactive iodine can be used as a way of shrinking the gland in more serious cases.
1 in 20
The proportion of people in the UK that suffer from thyroid disorders
Source: British Thyroid Foundation