Hyperthyroidism is the term for overactive tissue within the thyroid gland, resulting in overproduction and thus an excess of circulating free thyroid hormones: thyroxine (T4), triiodothyronine (T3), or both. The term is also often used more loosely to describe any syndrome of excess thyroid hormone (more properly termed hyperthyroxinemia), regardless of the source.
What are the symptoms of hyperthyroidism?
Hyperthyroidism is suggested by several signs and symptoms; however, patients with mild disease usually experience no symptoms. In patients older than 70 years, the typical signs and symptoms also may be absent. In general, the symptoms become more obvious as the degree of hyperthyroidism increases.
Major clinical signs include weight loss (often accompanied by a ravenous appetite), anxiety, intolerance to heat, fatigue, hair loss, weakness, hyperactivity, irritability, apathy, depression, polyuria, polydipsia, and sweating. Additionally, patients may present with a variety of symptoms such as palpitations and arrhythmias (notably atrial fibrillation), shortness of breath (dyspnea), loss of libido, nausea, vomiting, osteoporosis and diarrhea. In the elderly, these classical symptoms may not be present and they may present only with fatigue and weight loss leading to apathetic hyperthyroidism. Thyrotoxic crisis comes when the sick person is having stress.
Following an infection or a stressful event such as surgery, people with hyperthyroidism may develop a severe form of the condition called thyroid storm. Symptoms include:
Extremely high temperature
Severe diarrhea leading to dehydration
Causes of Hyperthyroidism
Your thyroid is a butterfly-shaped gland located at the base of your neck, just below your Adam's apple. Although it weighs less than an ounce, the thyroid gland has an enormous impact on your health. Every aspect of your metabolism is regulated by thyroid hormones.
How is hyperthyroidism diagnosed?
Your doctor will ask you about your symptoms and do a physical exam. Then he or she will order blood tests to see how much thyroid hormone your body is making.
Sometimes hyperthyroidism is found while you are having a test for another reason. You may be surprised to find out that you have this problem.
Treatment of Hyperthyroidism
Treatment varies depending on the cause of the condition and the severity of symptoms. Hyperthyroidism is usually treated with antithyroid medications, radioactive iodine (which destroys the thyroid and stops the excess production of hormones), or surgery to remove the thyroid.
If the thyroid must be removed with radiation or surgery, replacement thyroid hormones must be taken for the rest of the person's life.
Radioactive Iodine -- This is the preferred treatment of hyperthyroidism caused by Graves' disease. A radioactive iodine tablet is ingested and then taken up by thyroid cells. These overactive cells are damaged so that the thyroid can shrink in size and produce hormones at normal levels. Although this is a safe treatment, most people eventually become hypothyroid after radioactive iodine therapy and therefore require lifelong thyroid hormone replacement therapy. Radioactive iodine therapy cannot be given to pregnant women or those who are breastfeeding.
Anti-thyroid medications. These medications gradually reduce signs and symptoms of hyperthyroidism by preventing your thyroid gland from producing excess amounts of hormones. They include propylthiouracil and methimazole (Tapazole). Symptoms usually begin to improve in six to 12 weeks, but treatment with anti-thyroid medications typically continues at least a year and often longer. For some people, this clears up the problem permanently, but other people may experience a relapse.
