Thyroid Diseases

The thyroid is a butterfly-shaped gland that site in the neck under the Adam's apple. It regulates the body's metabolism by sending thyroid hormone to the organs through the blood. Two conditions, an overactive thyroid gland (hyperthyroidism) and an underactive thyroid gland (hypothyroidism) can result when the thyroid isn't working right.


An overactive thyroid gland generates too much thyroid hormone, which speeds up metabolism. Common symptoms of hyperthyroidism include:

·       rapid heart rate

·       frequent bowel movements, even diarrhea

·       excessive perspiration

·       weakness

·       insomnia

·       irritability and anxiety

·       increased appetite

·       weight loss

The first line of treatment for an overactive thyroid gland is drug therapy. If that doesn't resolve the problem, a dose of radioactive iodine may fix the problem by destroying thyroid cells. Sometimes the treatment damages so much of the gland that it can't produce enough thyroid hormone and it becomes necessary to take thyroid hormone. Surgery to remove some of the thyroid gland can be an option when other treatments don't work or aren't advisable.


An underactive thyroid gland doesn't generate enough thyroid hormone. This condition, which slows metabolism, is increasingly common with age. It can also be caused by Hashimoto's disease, a condition in which the body's immune system attacks the thyroid gland, or by thyroiditis, an inflammation of the gland.

Symptoms of hypothyroidism include:

·       fatigue

·       constipation

·       dry skin

·       muscle pain

·       hair loss

·       weight gain


Hypothyroidism is usually treated by taking thyroid hormone.

Thyroid Diseases Articles

Thyroid hormone: How it affects your heart

Located at the base of the throat, the butterfly-shaped thyroid gland releases hormones that affect every organ in the body—especially the heart. Too little thyroid hormone (hypothyroidism) slows the heart rate and may boost blood pressure and cholesterol levels. Too much thyroid hormone (hyperthyroidism) can cause the heart to beat harder and faster and may trigger abnormal heart rhythms and high blood pressure. A simple blood test can diagnose thyroid problems, and treatment may improve heart-related problems. More »

The lowdown on thyroid slowdown

Low thyroid hormone production, or hypothyroidism, can bring on a range of symptoms that may easily be confused with aging. A guide to hypothyroidism and how to treat it. More »

Could those common symptoms be thyroid trouble?

Sluggishness, fuzzy thinking, and unexplained weight gain are often missed as symptoms of an underactive thyroid. Harvard experts say it’s because the symptoms are often nonspecific, and since older adults generally have more of these nonspecific symptoms, they are even more likely to miss the problem. An underactive thyroid is diagnosed by measuring the level of thyroid-stimulating hormone (TSH) in the blood. The condition is treated with synthetic thyroid hormones called levothyroxine sodium (Synthroid, Levoxyl). (Locked) More »

How thyroid hormone affects the heart

The thyroid gland secretes hormones that regulate metabolism and energy levels. When it produces too little thyroid hormone, the heart can lose pumping strength, and cholesterol and blood pressure rise. Too much thyroid hormone can cause the heart to race and raises the risk of developing heart failure. Anyone with heart disease who has the symptoms of thyroid trouble should see their cardiologist or primary care doctor for simple blood test. (Locked) More »

Could you have a thyroid problem-and not know it?

  Many older women have an underactive or overactive thyroid gland that doesn’t quite meet the criteria for hypothyroidism or hyperthyroidism. This is called a subclinical thyroid problem. A simple blood test can reveal a subclinical thyroid problem. Subclinical hypothyroidism often does not need to be treated. Subclinical hyperthyroidism is often treated to prevent bone loss and heart problems.   (Locked) More »

When depression starts in the neck

Treating an underactive thyroid gland may improve mood. When someone develops depression, the brain usually becomes the focus of attention. But other organs can be the source of the problem. A common example is when the thyroid gland produces too little hormone — a condition known as hypothyroidism. Nearly 10 million Americans suffer from hypothyroidism. The condition is much more common in women than in men, and becomes more prevalent with age. As many as one in five women will develop hypothyroidism by age 60. Although researchers aren't entirely sure why there is a link between hypothyroidism and depression, it is likely that some people are taking antidepressants when they should really be taking thyroid medication. Here is a brief review of when clinicians and patients should consider hypothyroidism as a possible cause of low mood — and what to do next. More »

Thyroid deficiency and mental health

Researchers are exploring a potential link between thyroid deficiency and mental health problems. Though the findings are inconsistent, there is evidence that thyroid medication can help those with depression, even if their thyroid function is normal. More »

Thyroid Gland Disorders

For decades, Levothyroxine sodium, the most popular thyroid hormone for replacement therapy, had not been required to go through the Food and Drug Administration's approval process. But in 1997, the FDA reclassified all oral levothyroxine products as "new drugs," obligating the manufacturers to meet approved New Drug Applications (NDAs) before August 14, 2001. A history of potency and stability problems with orally administered levothyroxine sodium products resulted in the agency's decision.Two levothyroxine sodium products, Unithroid and Levoxyl, have recently been approved by the FDA to treat hypothyroidism. And now the FDA is issuing guidance regarding the transition of patients from unapproved to these approved products, and the handling of those products being marketed without an approved application. The FDA will gradually do away with the unapproved products to allow manufacturers of approved products to expand to meet demand and to give patients and health care providers enough time for a clean transition.Two of the most common formulations that are being phased out are Synthroid and Levothroid. Manufacturers of unapproved oral levothyroxine sodium drug products without an NDA pending with the FDA must cease distribution by August 14, 2001.August 2001 Update Back to Top Graves' disease is the most common cause of hyperthyroidism, an overactivity of the thyroid gland that results in too much thyroid hormone circulating through the body. The high thyroid level raises the body's metabolism, causing frequent bowel movements, increased heart rate, irritability, and anxiety, as well as an increased appetite partnered with weight loss. In addition, about one in five people with Graves' disease has bulging eyes. The condition is most common in young to middle-aged women.Doctors usually treat Graves' disease with antithyroid medicines, radioactive iodine treatment, or surgery. The goal of treatment is to induce long-term remission, that is, to permanently reduce the amount of hormone the thyroid gland produces. Most often, patients find antithyroid medicines effective while they are on them, but hyperthyroidism often returns once the drugs are stopped. Radioactive iodine and surgery, on the other hand, destroy or remove so much of the thyroid gland that it no longer produces enough thyroid hormone. As a result, patients need to take thyroid pills for the rest of their lives. Until now, it has been difficult for physicians to predict which treatment will be more effective for which patients.A new study, published in the March 2000 The Journal of Clinical Endocrinology & Metabolism, shows that patients under 40 and men do not respond as well to antithyroid medicines, and that men are less likely to be successfully treated with only one dose of radioiodine therapy. The researchers followed 423 patients for six months after they completed therapy. Of the patients, 314 received antithyroid medicines (usually an 18-month course of carbimazole) and 109 received radioiodine therapy.Of the patients taking antithyroid medicines, only 37% remained in remission six months after treatment. Of those, men were significantly less likely than women (20% vs. 40%) to remain in remission, and patients younger than 40 were significantly less likely than patients over 40 (33% vs. 48%) to stay in remission. Men were also significantly less likely than women (47% vs. 74%) to enter remission after one dose of radioiodine therapy.In response to these findings, the researchers proposed that men and patients younger than 40 receive early treatment with radioiodine therapy or surgery, since antithyroid medicines are unlikely to lead to remission. In addition, they suggest further research to investigate whether higher initial doses of radioiodine may be appropriate for male patients.To learn more about Graves' disease, see page 844 of the Family Health Guide. More »