What is Hypothyroidism?

Hypothyroidism is a condition in which the thyroid gland does not produce enough thyroid hormone. Thyroid hormone is made by the thyroid gland which is a butterfly-shaped gland in the front of the neck. It produces the hormones thyroxine (T4) and triiodothyronine (T3), which control metabolism. This affects how many calories you burn, how warm you feel, how much you weigh, and how the bodies handles many other vital functions of the cardiovascular, gastrointestinal, and nervous systems. Hypothyroidism results in a slower metabolism and slower heartbeat.

The Thyroid Gland © 2009 Nucleus Medical Art, Inc.

The most common form of hypothyroidism is Hashimoto’s thyroiditis. This condition occurs when your immune system produces antibodies that attack the cells of the thyroid gland, resulting in chronic thyroid...

A risk factor is something that increases your likelihood of getting a disease or condition.

It is possible to develop hypothyroidism with or without the risk factors listed below. However, the more risk factors you have, the greater your likelihood of developing hypothyroidism. If you have a number of risk factors, ask your healthcare provider what you can do to reduce your risk.

Medical Conditions

There are several medical conditions known to increase your risk of hypothyroidism. These include:

• Pregnancy—Five to eight percent of women develop postpartum thyroiditis. This condition is characterized by hyperthyroidism that is followed by hypothyroidism. Improvement usually results without treatment, but recurrences can occur and treatment is sometimes needed. This...

Symptoms usually come on gradually, over weeks or months. Therefore, you may have hypothyroidism for a long time, even years, before you realize you are ill. If you are an older adult, it may be even harder to recognize you are ill because instead of getting the typical symptoms of hypothyroidism, you may just gain weight or feel tired. Symptoms vary with the severity of the hypothyroidism and the length of time your body has lacked the proper amount of thyroid hormone.

You may have only one of these symptoms, but usually patients have a combination. Occasionally, patients with hypothyroidism have no symptoms at all, or the symptoms are so subtle they go unnoticed for a long period of time.

Symptoms include:

• Enlargement of the thyroid gland, called goiter (not always present) ...

The doctor will perform a physical exam and ask about your symptoms and medical/family history. Hypothyriodism is often found in families. The exam may reveal a goiter (enlarged thyroid), slow reflexes, dry skin, slow and hoarse speech, and/or a large tongue.

Your doctor may also do the following tests:

Blood Tests—Blood tests measure the level of thyroid hormones and thyroid antibodies. The diagnosis of hypothyroidism is made if the serum level of thyroid stimulating hormone (TSH) is elevated, and if the levels of serum free T4 (free thyroxine), and sometimes total T3, are low. These results mean that the thyroid gland is not making enough thyroid hormone.

The presence of thyroid antibodies may also signal autoimmune hypothyroidism, such as Hashimoto's thyroiditis, but...

Several drugs may cause hypothyroidism, but the association is not definitive. Some examples are:

• Perchlorate
• Lithium
• Thionamides
• Sulfonamides
• Ketoconazole
• Large doses of iodine
• Interleukin II
• Interferon
• Sunitinib

Although rare in the United States, iodine deficiency can cause hypothyroidism. A varied American diet and the use of iodized salt can avoid this nutritional deficiency. Your doctor or a registered dietitian can help you to identify foods rich in iodine, such as shellfish, iodized salt, breads, and cereals.

American Association of Clinical Endocrinologists (AACE)

Address:

245 Riverside AVE, STE 200
Jacksonville, FL 32204

Internet address:

http://www.aace.com

Description of services provided:

This organization, the primary professional association for practicing endocrinologists, with over 5,200 members worldwide, offers resources for the public and professionals.

American Thyroid Association

Address:

6066 Leesburg Pike, Suite 550
Falls Church, VA. 22041

Internet address:

http://www.thyroid.org

Description of services provided:

This is an official site for both patients and professionals of the highly respected and authoritarian organization. There are information sheets for patients, lists of recommended books, and lists...