Toxic nodular goiter: MedlinePlus Medical Encyclopedia

Toxic nodular goiter involves an enlarged thyroid gland. The gland contains areas that have increased in size and formed nodules. One or more of these nodules produce too much thyroid hormone.

Toxic nodular goiter starts from an existing

simple goiter

. It occurs most often in older adults. Risk factors include being female and over 55 years old. This disorder is rare in children. Most people who develop it have had a goiter with nodules for many years. Sometimes the thyroid gland is only slightly enlarged, and the goiter was not already diagnosed.

Sometimes, people with toxic multinodular goiter will develop high thyroid hormone levels for the first time after:

Taking iodine through a vein (

intravenously

) or by mouth. The iodine may be used as contrast for a

CT scan

or

heart catheterization

(most common).

Taking medicines that contain iodine, such as amiodarone.

Moving from a country with iodine deficiency to a country with a lot of iodine in the diet.

Symptoms may include any of the following:

Fatigue

Frequent bowel movements

Heat intolerance

Increased appetite

Increased sweating

Irregular menstrual period (in women)

Muscle cramps

Nervousness

Restlessness

Weight loss

Older adults may have symptoms that are less specific. These may include:

Weakness and fatigue

Palpitations

and chest pain or pressure

Changes in memory and mood

Toxic nodular goiter does not cause the bulging eyes that can occur with

Graves disease

. Graves disease is an autoimmune disorder that leads to an overactive thyroid gland (

hyperthyroidism

) without any nodules.

Beta-blockers can control some of the symptoms of hyperthyroidism until thyroid hormone levels in the body are under control.

Certain medicines can block or change how the thyroid gland uses iodine. These may be used to control the overactive thyroid gland in any of the following cases:

Before surgery or radioiodine therapy occurs

As a long term treatment

Radioiodine therapy may be used. Radioactive iodine is given by mouth. It concentrates in the overactive thyroid tissue and causes damage. In some cases, thyroid hormone replacement is needed afterward.

Surgery to remove the thyroid may be done when:

A very large goiter or a goiter is causing symptoms by making it hard to breathe or swallow

Thyroid cancer

is present

Rapid treatment is needed

Toxic nodular goiter is mainly a disease of older adults. So, other

chronic

health problems may affect the outcome of this condition. An older adult may be less able to tolerate the effect of the disease on the heart. However, the condition is often treatable with medicines.

Heart complications:

Heart failure

Irregular heartbeat (

atrial fibrillation

)

Rapid heart rate

Other complications:

Bone loss leading to

osteoporosis

Thyroid crisis or storm is a sudden worsening of hyperthyroidism symptoms. It may occur with infection or stress. Thyroid crisis may cause:

Abdominal pain

Decreased mental alertness

Fever

People with this condition need to go to the hospital right away.

Complications of having a very large goiter may include difficulty breathing or swallowing. This is due to pressure on the airway passage (trachea) or esophagus, which lies behind the thyroid.

Contact your health care provider if you have symptoms of this disorder listed above. Follow your provider's instructions for follow-up visits.

To prevent toxic nodular goiter, treat hyperthyroidism and simple goiter as your provider suggests.

Toxic multinodular goiter; Plummer disease; Thyrotoxicosis - nodular goiter; Overactive thyroid - toxic nodular goiter; Hyperthyroidism - toxic nodular goiter; Toxic multinodular goiter; MNG

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Pearce EN, Hollenberg AN. Thyroid. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 207.

Ullmann T, Kim J, Lindeman B, Sosa JA. The Thyroid. In: Tyler DS, Hayes-Dixon A, Hines OJ, et al, eds. Sabiston Textbook of Surgery. 22nd ed. Philadelphia, PA: Elsevier; 2026:chap 73.

Updated by: Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.