3 Ways to Treat an Overactive Thyroid

A Look at Antithyroid Drugs, Radioactive Iodine and Surgery

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Hyperthyroidism—an overactive thyroid—can be treated with three different approaches:

Conventional medicine offers no treatment or cure for the underlying autoimmune problem that causes Graves' disease.

The focus for those with hyperthyroidism or Graves' disease, therefore, is to normalize thyroid function, if possible, and minimize any symptoms and side effects of the overactive thyroid.

Antithyroid Drug Treatment

Antithyroid drugs have been in use since the 1940s. They are given to help normalize the thyroid levels and eliminate symptoms by making it more difficult for the body to use iodine to produce the thyroid hormone. There are two key antithyroid drugs:

Methimazole - Methimazole (pronounced meth-IM-a-zole), also known by its brand name, Tapazole (pronounced tap-UH-zole) and sometimes called "thiamazole," is used around the world.

Propylthiouracil - Propylthiouracil (pronounced proe-pill-thye-oh-YOOR-a-sill) is usually abbreviated as PTU. There are no brand names of PTU in the United States; only generic PTU is available. PTU has two effects: not only does it inhibit the thyroid from using iodine to produce thyroid hormone, but it also inhibits T4-to-T3 conversion.

Carbimazole - Carbimazole (pronounced car-BIM-a-zole) metabolizes to methimazole and is known by its brand name Neo-Mercazole.

Along with PTU, and methimazole, it is used in the United Kingdom and in other places outside the United States.

Methimazole is the preferred antithyroid drug in the United States, except during the first trimester of pregnancy. Because of the risk of liver damage, PTU is not recommended, especially for children, and is only recommended by the FDA in cases where radioactive iodine or surgery are not options, and methimazole is ineffective or can not be tolerated.

More information on antithyroid drugs is available in the following articles:

Radioactive Iodine Treatment

In the United States, Radioactive Iodine (RAI) is a common treatment for most people with Graves' disease and hyperthyroidism. Some other terms sometimes used to describe RAI include:

  • radioiodine ablation
  • radioactive iodine ablation
  • thyroid ablation
  • ablation therapy
  • chemical thyroidectomy
  • chemical surgery
  • radioactive cocktail

RAI is given as a single dose, in a capsule or drink.

After you've ingested the RAI, the iodine targets and enters the thyroid, where it radiates your thyroid cells, damaging and killing them. Your thyroid shrinks, and thyroid function slows down, reversing the hyperthyroidism.

Whether or not to continue using antithyroid drugs right up until RAI is controversial. Some practitioners recommend using the antithyroid drugs right up until the surgery, to keep the thyroid somewhat suppressed so that there is not a flare-up on hyperthyroidism post-RAI. Others discontinue antithyroid drug use prior to RAI, because of evidence that antithyroid drugs may reduce the effectiveness of RAI. Specifically, according to research, methimazole and carbimazole can be taken up to 3 to 5 days before RAI without reducing the effectiveness of the RAI, but because PTU takes longer to clear out of your system, it should be stopped at least two weeks before RAI. (Note: Some practitioners will switch their PTU patients over to Tapazole in the weeks prior to RAI, so that antithyroid drug therapy doesn't need to be stopped quite so early.)

In the United States, patients receiving doses of RAI less than 30 millicuries are not hospitalized. In Europe, most RAI patients are hospitalized to avoid exposing others to radiation.

If you have RAI in the United States, your doctor will discuss the radiation level and any precautions you might need to take to protect your family or the public.

Generally, however, in the first 24 hours after RAI, avoid intimate contact and kissing. In the first five days or so after RAI, limit exposure to young children and pregnant women, and, in particular, avoid carrying children in a way that they will be exposed to your thyroid area. Also avoid any thyroid-to-thyroid contact. Experts recommend that you drink a lot of water—some say at least 4 glasses a day—to help flush the RAI out of your system, sleep alone and use a bathroom apart from the rest of your family, if possible.

A very small percentage of patients are at risk of life-threatening thyroid storm after RAI. Read this article on Thyroid Storm for an overview of the risks and symptoms.

RAI can have some side effects, including nausea, vomiting, sore throat and swelling of saliva glands, but they are usually temporary.

The effects of RAI on the thyroid may begin to be felt as early as four weeks after treatment, and some patients become hypothyroid soon thereafter. It usually takes two to three months for the RAI to effectively slow down the thyroid in most patients.

Ultimately, most patients do become hypothyroid. Research has shown that, in fact, 25 to 50% of patients are hypothyroid a year after RAI, and 5% more become hypothyroid each year, for 10 years; 90% are hypothyroid.

Periodic evaluation of thyroid function is, therefore, important, and once hypothyroidism is detected, patients should start thyroid hormone replacement to prevent symptoms of an underactive thyroid.

An estimated 30% of patients who receive RAI will actually need a second RAI treatment later. Typically, these patients had a small initial dose, had a very enlarged thyroid or other complicating factors.

There is a degree of controversy over RAI. The majority of North American endocrinologists tend to prefer RAI -- almost always as a permanent, irreversible treatment -- versus antithyroid drugs. Many also believe it is safe to use in women of childbearing age and children.

This is in contrast to Europe, where antithyroid drugs are the preferred first treatment, and RAI and surgery are used for those patients who don't respond to the medication. European endocrinologists also tend to be more cautious and are far less likely to use RAI in women of childbearing age and children. Some more cautious practitioners in the United States, however, recommend that the first episode of Graves' disease should always be treated with antithyroid drugs. The key exception is in the case of patients 50 and older, who frequently should have RAI to reduce the possibility of hyperthyroidism-induced atrial fibrillation.

Additional information on the controversies over RAI is featured in the following articles:

RAI is not considered risky. In fact, the primary "risk" of RAI is actually lifelong hypothyroidism. While some practitioners and patients are concerned about possible cancer risks of RAI, most studies have found no increased risk of cancer, leukemia, infertility or birth defects associated with RAI. Some studies have found a slightly increased risk of thyroid and small bowel cancer after RAI. Further study of the long-term risks of RAI for Graves' disease and hyperthyroidism is clearly needed.

RAI is not given to pregnant women, as there are significant risks to the fetal thyroid development. Before getting pregnant, most doctors also recommend waiting from six months to a year after RAI to avoid any risk of residual radiation on the fetus.

Surgical Treatment

Thyroid surgery—known as thyroidectomy—is considered the last choice in the United States for treating an overactive thyroid. Surgery is, however, recommended in certain situations:

  • If antithyroid drugs and/or RAI have been unable to control the condition
  • If a patient has suspicious nodules or thyroid cancer has already been found
  • If a patient is experiencing an obstructed airway/difficulty breathing or swallowing
  • If a patient is pregnant and not responding to antithyroid drugs
  • If the patient has a very large goiter

Outside the United States, where surgery is more commonly used as a hyperthyroidism treatment, many practitioners recommend surgery rather than RAI for children, women of childbearing age who haven't responded to antithyroid drugs and women who want to get pregnant soon after treatment.

Surgery is considered very effective and can provide rapid relief of symptoms to most patients, particularly when they have a large goiter and/or severe symptoms. Surgery is, however, invasive and has some risks, including hypoparathyroidism and damage to the laryngeal nerve. In the hands of an experienced surgeon, these risks are low, usually less than 3%.

Surgical mortality from thyroid surgery is almost nonexistent.

Detailed information on thyroid surgery is featured in these articles:

Beta Blockers

While it's not a treatment for hyperthyroidism specifically, some people with hyperthyroidism are also treated with "beta adrenergic receptor antagonists"—known more commonly as beta-blockers—because they help alleviate the effects of excess thyroid hormone on the heart and circulation, especially rapid heart rate, blood pressure, palpitations, tremor and irregular rhythms. Beta blockers also reduce the breathing rate, reduce excessive sweating and heat intolerance and generally reduce feelings of nervousness and anxiety. Some beta-blockers also can help prevent T4-to-T3 conversion. They don't, however, slow the metabolic rate itself.

Propranolol (pronounced "proe PRAH no lall") is the most recommended and studied beta-blocker for hyperthyroidism. The most common brand name for propranolol is Inderal. While propranolol is considered the first beta-blocker to try for Graves' and hyperthyroidism patients, other beta-blockers sometimes given include atenolol (Tenormin) and metoprolol (Lopressor, Toprol XL).

The effects of most beta-blockers are usually fairly rapid, sometimes even within 10 to 15 minutes.

Beta blockers may not be recommended to patients with asthma, severe allergies, emphysema or any lung disease or bronchial conditions. Beta blockers also interact with a number of medications. You can check the interactions of any drugs at About.com's Drugs A to Z interactions checker.

Temporary Thyroid Problems

For the temporary or "self-limited" forms of hyperthyroidism (i.e., subacute thyroiditis, painless / silent thyroiditis, postpartum thyroiditis, Hashitoxicosis, Transient Hyperthyroidism of Hyperemesis Gravidarum (THHG)) the focus is primarily on treating the symptoms.

So, for example, pain relievers may be given for pain and inflammation or beta blockers for heart-related symptoms. Occasionally, an antithyroid drug is prescribed for a short time.

New Developments

The thyroid community is always looking for better ways to treat Graves' disease and hyperthyroidism. One promising new direction is the use of thyroid arterial embolization as a treatment option for Graves' disease. Another technique, argonplasma resection, allows for minimum blood loss during surgery, with less scarring and faster recovery. More thyroid surgery is now being done with endoscopy or laparoscopy, with incisions in either the breast or under the arm, so there is no visible scar on the neck and minimal scarring.

Holistic and Natural Approaches

Natural health practitioners recommend a variety of various natural, alternative medicine and integrative approaches to Graves' disease and hyperthyroidism. Dr. Richard Shames has developed a complementary antithyroid protocol, using a variety of supplements and foods, including l-carnitine, to help treat hyperthyroidism. These approaches are outlined in detail in the book Living Well With Graves' Disease and Hyperthyroidism. Author Kate Flax has detailed a variety of natural approaches to hyperthyroidism in her book Healing Options: A Report on Graves' Disease Treatments.

Choosing an Approach

With antithyroid drugs, treatment only has an effect while the medications are being taken, but remission is possible in some patients. RAI and surgery are permanent, irreversible treatments that almost always result in lifelong hypothyroidism for the patient. For this reason, some practitioners believe that antithyroid drugs should almost always be the first choice for treating an overactive thyroid, except in special circumstances.


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