Hyperthyroidism means that your thyroid gland is overactive, and producing too much thyroid hormone. The most common cause of hyperthyroidism is autoimmune Graves’ disease.
The symptoms of Graves’ disease often reflect a speeding up of your body’s processes and can include an elevated heart rate, elevated blood pressure, insomnia, anxiety, diarrhea and loose stools, sweating, and weight loss.
Conventional medicine has no treatments for the underlying autoimmunity that causes Graves’ disease, so treatment focuses on the hyperthyroid condition itself, with the goal of normalizing your thyroid function, reducing the amount of thyroid hormone being produced, and addressing the symptoms and side effects of your overactive thyroid.
There are three conventional ways to treat hyperthyroidism:
- Antithyroid drug treatment
- Ablation of the thyroid gland with radioactive iodine (RAI)
- Surgery — known as thyroidectomy — to partially or fully remove your thyroid
In late 2016, the American Thyroid Association (ATA) issued their “Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis.” The full text of the 2016 guidelines is available online as a PDF.
The ATA guidelines reviewed and made recommendations regarding evidence-based clinical guidelines for the treatment of hyperthyroidism, also called thyrotoxicosis, and the key steps involved in treatment.
Step 1: Find out the cause of the hyperthyroidism
The ATA guidelines recommend that the cause of the hyperthyroidism be identified before a specific treatment is recommended. Autoimmune Graves’ disease is the most common cause of hyperthyroidism. Other conditions that can cause hyperthyroidism include multiple nodules (toxic multinodular goiter), a benign thyroid tumor called a toxic adenoma, and thyroiditis (inflammatory conditions of the thyroid gland.) Determining the cause of your hyperthyroidism can involve:
- Blood testing of your thyroid hormones, including thyroid stimulating hormone (TSH), free thyroxine (free T4) and free triiodothyronine (free T3)
- Testing of your thyroid antibodies, including thyroid stimulating antibodies (TSI) and thyrotropin receptor antibodies (TRAb) frequently seen in Graves’ disease
- Imaging tests such as ultrasound to identify goiter and nodules, and the radioactive iodine uptake (RAI-U) test to evaluate whether your nodules are producing excess hormone
2. Address elevated heart rate
The ATA guidelines recommend that any elevated heart rate or blood pressure — common symptoms of hyperthyroidism — be rapidly addressed with prescription beta-blocking drugs. This is especially important if your heart rate is more than 90 beats per minute, if you are a senior, or have a heart condition.
Beta blockers, also known as “beta adrenergic receptor antagonists,” work quickly, often within minutes, and have a number of effects:
- They help reduce a rapid heart rate.
- They lower your blood pressure.
- They can help regulate heart palpitations and rhythm irregularities.
- They help with heat sensitivity and sweating.
- They reduce feelings of anxiety.
- They can block some of the conversion of the T4 hormone into the active T3 hormone.
The most commonly recommended beta blocker for hyperthyroidism is propranolol (brand name Inderal). Other beta blockers that may be used include atenolol (brand name Tenormin) and metoprolol (brand names Lopressor and Toprol XL).
Beta blockers may not be recommended, however, if you have asthma, bronchial conditions or lung disease.
3. Choose a treatment
The next step is to determine which hyperthyroidism treatment — antithyroid drugs, RAI, or surgery — is recommended.
Antithyroid drugs are often recommended as a short-term or first course of treatment in several situations:
- If your hyperthyroidism is mild or subclinical
- If your hyperthyroidism is severe, and decisions are still being made regarding RAI versus surgery
- If you are hyperthyroid but do not have autoimmune Graves’ disease
- If you are pregnant, or you are breastfeeding and want to continue
- If you would not be able to adhere to the safety regulations after being treated with RAI
- If you have mild thyroid eye disease
Antithyroid drugs result in remission for some patients. You are at risk of a reoccurrence of your hyperthyroidism, but it allows you to temporarily or permanently avoid RAI and surgery,
RAI is recommended if you have previously reacted negatively or failed to respond to antithyroid drug treatment. If you are planning to become pregnant, you also need to be aware that you need to wait six months to a year after RAI before attempting to become pregnant. RAI allows you to avoid surgery or antithyroid drug side effects.
RAI is not typically a first-line recommendation in children, and according to the ATA guidelines, is usually not used to treat children under the age of 5.
RAI almost always results in hypothyroidism, and you will need to take thyroid hormone replacement medication.
Thyroid surgery, known as a thyroidectomy, is recommended in several situations:
- If you have a large goiter or nodules
- If your goiter or nodules are impairing breathing or swallowing, or cosmetically unsightly
- If you have moderate or severe thyroid eye disease
- If you have very high thyroid antibodies
- If you are pregnant, in your second trimester, and can’t take antithyroid drugs for any reason
Surgery is not recommended if you are at risk of surgery and anesthesia due to your age or other pre-existing conditions. Surgery is also not recommended during pregnancy unless urgently needed, and if so, it is performed only during the second trimester when it poses the lowest risk to your pregnancy.
After thyroid surgery, you will usually be hypothyroid and need to remain on thyroid hormone replacement medication for life.
Treatment option: Antithyroid drugs
Antithyroid drugs treat hyperthyroidism by blocking your body’s ability to use iodine to produce thyroid hormone. In the United States, two antithyroid drugs are used:
- Methimazole: the brand name is Tapazole
- Propylthiouracil (PTU): PTU is only available as a generic drug
Outside the United States, carbimazole (Neo-Mercazole) — a drug similar to methimazole — is also used.
The preferred drug in the U.S. is methimazole because PTU poses some risk of liver damage. PTU is only recommended when RAI, surgery, and methimazole are not options for you.
Note: Because of a slight increase in birth defects, methimazole is not used during the first trimester of pregnancy, when PTU is substituted.
When you are taking antithyroid drugs, your thyroid levels are typically measured within two to six weeks after starting treatment. Your dosage is adjusted until your levels are stabilized, and then testing is usually repeated and dosage adjusted if needed every one to two months.
When you are taking antithyroid drugs you may experience a remission — usually after a year or more on the medication — as your thyroid hormone and antibody levels return to the reference range. In this situation, your doctor will slowly reduce your dose of antithyroid drugs, and you may even have a period where you require no medication. You should have regular monitoring, however, and be aware of symptoms that would indicate that your hyperthyroidism has recurred.
Negative reactions or side effects of antithyroid drugs are not common, but can include:
- Allergic reactions
- Skin rash
- Itchy skin
- Hair loss
- Pain in joints
- Abdominal pain or nausea
If you have any of these reactions, you should notify your doctor right away.
A very small subset of patients can develop agranulocytosis, a rare and very serious complication of antithyroid drugs. Agranulocytosis makes your body unable to fight off infection, and while it’s a risk in both drugs, it is more common when taking PTU, and is more likely when you are in the early stages of antithyroid drug treatment, or when you are taking either drug at higher doses.
If you develop any signs of infection while taking antithyroid drugs — especially sore throat or fever — you need to see your doctor immediately. The guidelines state that your doctor should order a differential white blood cell (WBC) test if you are sick with a fever and/or upon the onset of a sore throat, to identify the possible onset of agranulocytosis before it becomes life-threatening.
Treatment option: Radioactive iodine (RAI)
Radioactive iodine (RAI) is also known by a number of other names, including radioactive iodine ablation, ablation therapy, thyroid ablation, and chemical thyroidectomy.
RAI is typically given as a capsule. After you swallow the RAI, the radioactive iodine goes to your thyroid, where the radioactivity damages and kills off your thyroid cells. This prevents your thyroid from producing thyroid hormone, which then helps resolve your hyperthyroidism.
In some cases, your doctor may have you take antithyroid drugs prior to RAI. In other cases, doctors may have you stop up to two weeks prior to RAI treatment to ensure that the drug does not prevent the RAI from working effectively.
Your doctor will provide you with specific guidelines regarding radiation safety after your RAI treatment. You will usually not be isolated, but for at a designated period of time you will need to avoid close contact with and proximity to others, especially children, pregnant women, and pets.
You may have some temporary side effects from RAI including nausea, vomiting, a metallic taste in your mouth, a sore throat, swelling of your saliva glands, and a dry mouth. These usually resolve fairly quickly after your RAI treatment.
It can take from four weeks to up to six months for the full effects of the RAI on your thyroid, and a return to normal levels (or the onset of hypothyroidism).
There may be a period when your thyroid is normal and you require no medication. Over time, however, you are likely to become hypothyroid. You should have regular thyroid testing and start thyroid hormone replacement treatment as soon as hypothyroidism is confirmed. After 10 years, 90 percent of people who have had RAI are hypothyroid and need thyroid hormone replacement medication.
In some cases, the initial RAI treatment may not resolve your hyperthyroidism, or you may have a later relapse of hyperthyroidism. This occurs in an estimated 30 percent of patients who receive RAI. In this case, you may need a second dose of RAI.
RAI is not given to you when you are pregnant because it can damage your baby’s thyroid. After RAI, doctors recommend you wait from six months to a year before getting pregnant, to protect your baby from any leftover radiation.
Treatment option: Surgery/thyroidectomy
Thyroid surgery — thyroidectomy — is more commonly used as a hyperthyroidism treatment outside the U.S., but it remains a treatment option, especially when a rapid solution is needed.
Thyroid surgery is considered a very safe surgery and can be done as an outpatient, or with a short hospital stay. There is usually a short recuperation period. Experts advise, however, that your surgery should be performed by an experienced, high-volume thyroid surgeon to reduce the risk of complications, which can include hypoparathyroidism, low calcium levels, or damage to your laryngeal nerve.
Prior to thyroid surgery, your doctor may treat you with antithyroid drugs, potassium iodide, steroid drugs, and/or beta blockers.
After surgery, once any excess thyroid hormone leaves your bloodstream, you will become hypothyroid for life, and require thyroid hormone replacement medication. You should have periodic thyroid testing after thyroidectomy so that you can receive treatment to coincide with the onset of hypothyroidism.
Note: If you have a partial thyroidectomy, you are still at risk of becoming hypothyroid and should be regularly monitored.
Ross Douglas S., et al. “2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis.” Thyroid. October 2016, 26(10): 1343-1421. doi:10.1089/thy.2016.0229. Online PDF.
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Mary Shomon is a thyroid disease, hormonal and autoimmune health writer, and patient advocate. For two decades, Mary has been a leading force advocating for more effective, patient-centered thyroid and hormonal health care. Mary is the New York Times bestselling author of “The Thyroid Diet Revolution,” “Your Healthy Pregnancy with Thyroid Disease,” “Living Well With Hypothyroidism,” and 10 other books on thyroid disease and integrative health. She co-stars in two PBS health specials, “Healthy Hormones,” and “Vibrant for Life.” Follow her on Twitter at @thyroidmary or at her Facebook communities: ThyroidSupport and ThyroidDiet.