Causes

The most common cause of hyperthyroidism, especially in young people, is Graves’ disease. Graves’ disease is caused by antibodies in the blood that stimulate the thyroid to grow and secrete excess thyroid hormone. It tends to run in families.

In elderly people a common cause of hyperthyroidism is toxic nodular goiter, or overactive thyroid nodules. Other causes of hyperthyroidism include:

• Inflammation of the thyroid gland from a viral infection
• Ingestion of excessive amounts of thyroid hormone
• Ingestion of excessive iodine

Symptoms

Symptoms of hyperthyroidism include:

• Weight loss
• Increased appetite
• Nervousness
• Irritability
• Heat intolerance
• Increased sweating
• Thinning of the skin
• Fine, brittle hair
• Shaky hands
• Racing heart
• Frequent bowel movements
• Menstrual irregularities in women
• Eyes that look enlarged
• Possible presence of goiter

To determine if you have hyperthyroidism, your doctor will do blood tests. If these tests suggest hyperthyroidism, you may also have other tests, such as a thyroid scan or a thyroid reuptake, to find out if you have Graves’ disease.

Treatment

If you have hyperthyroidism, the type of treatment will depend on many things, including your age, the type of hyperthyroidism, allergies to medication, and other conditions that may affect your health. The three most common types of treatment for hyperthyroidism are medications, radioactive iodine, and surgery.

Medications

The two classes of medication that are used most often to treat hyperthyroidism are beta-blockers and antithyroid medications.

Beta-blockers, such as propranolol and atenolol, do not lower thyroid hormone levels. However, they can reduce some hyperthyroid symptoms, such as rapid heart rate, palpitations, hand tremors, anxiety, and nervousness. If you are taking a large dose of beta-blockers, do not stop taking it suddenly. Talk to your doctor about gradually reducing the dose.

Antithyroid medications lower thyroid hormone levels in the blood by blocking thyroid hormone production from the overactive thyroid gland. Examples of antithyroid medications include propylthiouracil or methimazole. It usually takes 2 to 4 weeks of antithyroid drug treatment before the hyperthyroid symptoms improve, and it can be several months before thyroid function becomes normal. At that time the dosage is usually reduced.

Occasionally, antithyroid medications can lower your white blood cell count or cause toxic hepatitis, both of which are serious and require medical attention. If you have a fever, sore throat, mouth sores, or other symptoms of infection or if you have nausea, vomiting, or yellowing of the eyes, stop taking your medication and call your doctor right away.

Radioactive Iodine

Radioactive iodine treats hyperthyroidism by destroying some of the cells that make the thyroid hormone. Patients swallow a capsule or drink that contains radioiodine. The radioiodine goes into the bloodstream and is absorbed by the overactive thyroid cells. Over several weeks the radioiodine destroys the overactive thyroid cells, which helps the thyroid hormone return to normal. It may take up to 6 months for the full effect to be seen.

Sometimes, hyperthyroidism continues after radioiodine treatment. In these cases, a second radioiodine treatment may be needed.

Surgery

For some patients with hyperthyroidism, doctors recommend surgery. If a single nodule or lump of thyroid tissue is overactive, the surgeon removes this part of the thyroid and the rest of the thyroid usually returns to normal.

If many nodules or the entire thyroid gland is overactive, the entire thyroid gland is removed and hyperthyroidism will never again occur. However, to prevent hypothyroidism, you will have to take thyroid hormone tablets for the rest of your life.

Self-Care

Because your metabolism increases with hyperthyroidism, you may have lost weight. As thyroid hormone levels become normal, your metabolism will also return to normal and you may gain weight. During this time, it may be important to watch the number of calories and types of food that you eat.

As your heart rate returns to normal, aim for 30 minutes of activity on most days of the week. If you can’t do that much at once, do a little at a time. Regular activity has a lot of benefits. It can help control weight, boost your energy, and keep you physically fit.

Talk with your doctor if you have questions about maintaining a healthy weight or establishing an exercise program.