Thyroid Goiter: Causes & Treatments

A thyroid goiter is an enlarged thyroid gland. It is a treatable condition and is not usually dangerous. But the cause of the goiter needs to be properly identified to rule out thyroid cancer. Please continue reading to learn more about what causes thyroid goiter and the treatment options for this condition.

What is the thyroid gland, thyroid hormone, and thyroid stimulating hormone?

The thyroid gland is part of the body’s endocrine system. It is a small butterfly-shaped gland located in the neck. The thyroid makes two hormones called T3 and T4. These hormones play a role in important functions such as metabolism, heart rate, blood pressure, body temperature, digestion, muscle function, and brain development. Thyroid-stimulating hormone (TSH) is made by the pituitary gland in the brain to control thyroid function. It tells the thyroid gland to produce thyroid hormone.

When the levels of thyroid hormones are too high or too low, it can result in thyroid conditions such as overactive thyroid (hyperthyroidism or too much thyroid hormone) and underactive thyroid (hypothyroidism or not enough thyroid hormone). Hashimoto’s disease is an autoimmune disorder in which the immune system mistakenly attacks healthy thyroid cells, resulting in an inflammation of the thyroid and underactive thyroid, but it can sometimes cause overactive thyroid. Graves disease is an autoimmune disease that results in overproduction of thyroid hormones. Thyroid cancer is an abnormal growth of cells in the thyroid.

Healthcare providers can diagnose a thyroid disease with a physical examination and tests such as a blood test (thyroid function tests), antibody test, an imaging test such as ultrasound, MRI, or CT scan, a type of thyroid scan called a radioactive iodine scan, and thyroid biopsy.

What is thyroid goiter?

A goiter is an enlargement of the thyroid gland. It may cause no change in thyroid hormone levels, or it may cause an underactive thyroid gland or an overactive thyroid gland.

Is thyroid goiter the same as thyroid nodules?

Thyroid enlargement can be of the gland as a whole (simple goiter) or in the form of irregular lumps called thyroid nodules (nodular goiter or multinodular goiter).

What is the most common cause of thyroid goiter?

The most common cause of thyroid goiter worldwide is iodine deficiency (not enough iodine in the diet). However, in the United States, iodized table salt prevents goiter. Nonetheless, goiter affects around 5% of the US population. The cause of goiter in the US is usually some other factor that affects thyroid growth, such as overproduction or underproduction of thyroid hormones or thyroid nodules. Notably, too much iodine can also cause goiter in some people.

Goiter is four times more common in females than males and more common after age 40. Other risk factors include obesity, metabolic syndrome, insulin resistance, radiation exposure to the head and neck, and a family history of thyroid disorders. Taking certain medications, such as the heart medication amiodarone (Pacerone) or the psychiatric medication lithium (Lithobid), can also increase the risk of goiter.

What are the types of goiter?

The 3 main types of goiters are:

Simple goiter or diffuse goiter, in which the entire thyroid gland is enlarged and smooth in appearance.
Nodular goiter, in which a solid or cystic lump called a nodule develops in the goiter.
Multinodular goiter, in which there are multiple nodules in the thyroid that make it appear lumpy.

Goiters are also classified according to thyroid hormone levels:

Toxic goiter is when the enlarged thyroid gland produces too much thyroid hormone, resulting in abnormal levels of thyroid hormone.
Nontoxic goiter is when the thyroid is enlarged, but thyroid levels are normal (this is called euthyroid).

Your healthcare provider will use a combination of these terms to describe the type of goiter you have, for example, simple non-toxic goiter or toxic multinodular goiter.

What are the symptoms of having a goiter?

Some people with a thyroid goiter have no symptoms. The goiter is small and is only discovered incidentally during workup for some other health problem. In others, goiter symptoms and signs can include a visible swelling at the base of the neck. A large goiter can cause symptoms such as cough, difficulty breathing, difficulty swallowing, and voice changes.

If the thyroid produces less hormone as a result of goiter, the resultant hypothyroidism can cause symptoms such as fatigue, dry skin, increased cold sensitivity, muscle weakness, unexplained weight gain, and problems with memory and concentration.

On the other hand, if the goiter produces more thyroid hormone, the resultant hyperthyroidism can cause symptoms such as rapid heartbeat, increased heat sensitivity, unexplained weight loss, increased sweating, shakiness, nervousness, irritability, frequent bowel movements, muscle weakness, sleep difficulties, and changes in the menstrual cycle.

Do thyroid goiters go away?

A simple goiter may go away on its own without treatment. Multinodular goiters that are associated with a euthyroid state (normal thyroid hormone levels) do not typically require any treatment. However, if you have an enlargement of the thyroid, it is important to have it diagnosed by a healthcare provider to rule out more serious conditions, such as thyroid cancer, that require treatment.

What is the best treatment for thyroid goiter?

Treatment for goiter depends on the underlying cause. For example, if the cause is a lack of iodine in the diet, the treatment will consist of iodine supplements. If you have abnormal thyroid hormone levels, medication to normalize these levels may decrease the size of the goiter. Some of the medications used to reduce the size of a goiter include:

Levothyroxine (Levoxyl) and liothyronine (Cytomel) to increase hormone production in people with an underactive thyroid (too little hormone)
Anti-thyroid drugs such as methimazole (Tapazole) in people with a thyroid gland that is overactive
Beta blockers such as metoprolol (Lopressor) and atenolol (Tenormin) to manage the symptoms of hyperthyroidism (too much hormone)
Pain medications such as aspirin, ibuprofen, or naproxen to manage pain associated with thyroid inflammation

If you have compressive (pressure) symptoms, your doctor may recommend radiofrequency ablation (RFA) to reduce the size of the thyroid goiter. For an overactive thyroid gland, your doctor may prescribe radioactive iodine treatment in which you take a dose of radioactive iodine by mouth, and the drug destroys thyroid cells.

In some cases, surgical removal of a part of or the entire thyroid gland is necessary with a procedure called thyroidectomy if the goiter is causing symptoms. You will need to take thyroid replacement therapy lifelong after this surgery.

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