Thyroid Gland

The thyroid gland is a butterfly-shaped endocrine gland located in the front, lower portion of the neck, in front of the windpipe. The thyroid gland makes, stores and releases thyroid hormone into your bloodstream and helps control your body’s functions. Your brain regulates the amount of hormone made by your body.


A goiter is an enlarged thyroid gland. You may see or feel a swelling on one or both sides of your neck or notice your collar and/or necklaces have become tighter. If a goiter causes symptoms or problems, a partial or total thyroidectomy may be needed.


If your thyroid gland produces too much thyroid hormone, you may have hyperthyroidism. Having too much thyroid hormone causes your body to speed up, resulting in nervousness, a fast heart rate and unexplained weight loss, among other symptoms.

The most common form of hyperthyroidism is Graves’ disease (diffuse toxic goiter), in which the body’s immune system overstimulates the thyroid. Graves’ disease may cause bulging of the eyes (exophthalmus). Other causes may be toxic adenoma or toxic multinodular goiter. A nodule (lump) in the thyroid gland can cause hyperthyroidism if the cells in the nodule produce more hormones than the rest of the gland. Graves’ disease may be treated with ablation using radioactive iodine or with surgery, depending on the clinical situation. After treatment, patients usually are followed medically, and replacement therapy is begun. Surgical removal of the goiter may be necessary to relieve pressure symptoms.

Ablation with radioactive iodine works because of the way the thyroid functions. The thyroid is the only system in the body that absorbs iodine. So if iodine is injected (or taken by mouth), the radioactive iodine goes to the thyroid, and as it is absorbed, it kills the thyroid cells.

Surgery can include removal of the entire thyroid gland or of part of the gland.


If your gland produces too little thyroid hormone, you may have hypothyroidism. Having too little thyroid hormone causes your body to slow down, resulting in decreased energy level, feeling cold, feeling depressed, weight gain and other symptoms. The most common cause of hypothyroidism is Hashimoto’s thyroiditis, in which the body’s immune system mistakes the thyroid gland as a foreign body it needs to attack. It also may result from a lack of iodine or failure to take thyroid replacement medication after the thyroid gland has been removed or after ablation.

Diagnosis and Treatments

Thyroid nodules often are discovered by the patient. If you notice a lump in your neck, or your collar or necklace is becoming tighter, see your physician. Hoarseness, difficulty swallowing, chronic cough, history of radiation or family history of thyroid cancer, symptoms of hyperthyroidism, and symptoms of hypothyroidism all should be reported to your doctor. The doctor will order laboratory tests, examine your neck and possibly order a biopsy called a fine-needle aspiration. Based on the outcome of your screening tests, your doctor will recommend a treatment program.