Thyroid Medications

The appropriate drug for you depends on what thyroid disease you have

Thyroid medications are used to treat different conditions, including hypothyroidism (underactive thyroid), hyperthyroidism (overactive thyroid), and thyroid cancer.

Hypothyroidism is treated with hormone-replacement therapy. Synthroid (levothyroxine) is the most widely used drug for hypothyroidism.

Hyperthyroidism is treated with anti-thyroid drugs, such as Tapazole (methimazole), or radioactive iodine. Beta-blockers are also used to relieve symptoms of an overactive thyroid.

In addition, people with thyroid cancer may require hormone-replacement therapy, radioactive iodine therapy, or chemotherapy.

This article explains how various thyroid conditions are treated and common thyroid medication names.

What is hypothyroidism?
Verywell / Emily Roberts

Hypothyroidism Medications

The role of the thyroid gland is to produce the hormones thyroxine (T4) and triiodothyronine (T3). These thyroid hormones regulate everything from heart rate and body temperature to respiratory function and menstrual cycles.

When the thyroid is underactive, it is called hypothyroidism. The thyroid gland may become underactive for numerous reasons, including:

When your thyroid is underactive, it produces insufficient thyroid hormone. This deficiency leads to various symptoms that affect one or more organ systems. Symptoms can range in severity from mild to debilitating.

Hypothyroid Medication Names
 Brand Name  Generic Name
 Armour Thyroid  natural thyroid
 Cytomel  liothyronine
 Levothyroid  levothyroxine
 Levoxyl   levothyroxine  
 Nature-throid  natural thyroid
 Synthroid   levothyroxine
 Thyrolar  liotrix
 Tirosint  levothyroxine
 Triostat  liothyronine
 Unithroid   levothyroxine
 Westhroid   natural thyroid

Treatment Goals

To restore sufficient thyroid hormone levels in the body, people with hypothyroidism usually take thyroid hormone replacement medication. However, medication may not always be necessary for some circumstances, such as when an underactive thyroid gland is transient (temporary).

For example, some cases of thyroiditis (thyroid inflammation) are caused by reversible situations, such as a response to a medication, infection, or following pregnancy. Therefore, they may not require medication.

There are four main goals of thyroid hormone replacement medication:

  • Alleviate symptoms of hypothyroidism
  • Normalize the thyroid stimulating hormone (TSH) level
  • Reduce the size of an enlarged thyroid (goiter) if present
  • Avoid over-treatment (becoming hyperthyroid)

Levothyroxine

Levothyroxine—also called l-thyroxine and L-T4—is a synthetic form of the T4 (thyroxine) hormone. T4 is the storage hormone, which your body must convert into T3, the active hormone, for your cells to use.

Levothyroxine is the first-line treatment drug for treating hypothyroidism. In the United States, brand names include:

Liothyronine

Liothyronine is a synthetic form of T3 (triiodothyronine). Brand names of liothyronine in the United States are Cytomel and Triostat.

For the most part, experts recommend T4-monotherapy (treatment with only T4) and not combination T4/T3 therapy for treating hypothyroidism. Therefore, healthcare providers do not commonly prescribe this medication.

Research is ongoing about whether combination T4/T3 therapy may benefit a subgroup of people with hypothyroidism who have a specific genetic mutation.

Natural Desiccated Thyroid

Natural desiccated thyroid—also known as NDT, natural thyroid, or porcine thyroid—is a prescription drug derived from the dried thyroid glands of pigs. NDT contains both T4 and T3.

Common brands are Armour Thyroid and Nature-throid. A generic is also available.

Most endocrinologists (doctors specializing in hormone-related conditions) do not support or prescribe natural desiccated thyroid drugs. That is because they are combination drugs and the ratio of T4 to T3 in animals does not match the ratio in humans. That said, certain select people may respond well to NDT.

Hyperthyroidism Medications

Hyperthyroidism means the thyroid gland is overactive, producing too much thyroid hormone. There are multiple causes of hyperthyroidism, including:

Moreover, a phase of Hashimoto’s disease can also cause hyperthyroidism in the same way it causes hypothyroidism.

Hyperthyroid Medication Names
 Brand Name  Generic Name
 Corgard   nadolol 
 Inderal  propranolol
 Lopressor  metoprolol 
 Propycil   propylthioracil 
 Radioactive iodine  iodine 131 (I-131)
 Tapazole  methimazole 

Treatment Goals

The treatment of hyperthyroidism with Grave's disease or hit nodules is generally more complex than hypothyroidism, requiring one or more of the following treatments:

The only medications for hyperthyroidism are anti-thyroid drugs. There are currently two approved for treating hyperthyroidism in the United States.

  • Tapazole (methimazole, or MMI)
  • Propylthiouracil (PTU)

Tapazole (methimazole)

The anti-thyroid drug Tapazole inhibits the thyroid from using iodine—usually from the diet—to produce thyroid hormone. You generally take this medication once a day.

Tapazole has fewer side effects and reverses hyperthyroidism more quickly than PTU. Its effectiveness makes it the preferred anti-thyroid drug choice.

Propylthiouracil (PTU)

Like Tapazole, PTU inhibits the thyroid gland from using iodine. Thus, it slows the overproduction of thyroid hormone. It also inhibits the conversion of the thyroid hormone T4 into T3.

PTU has a short-acting timespan. That means people taking this medication usually need to take the drug two to three times per day to effectively lower thyroid hormone levels.

PTU has more side effects than other anti-thyroid drugs. Therefore, it is the preferred drug for hyperthyroidism only in a few situations, including:

  • Early pregnancy
  • Severe thyroid storm (when the body releases exceptionally high levels of thyroid hormones)
  • Someone experiences serious side effects from Tapazole

Beta-Blockers

Beta-blockers, like Inderal (propranolol), block beta receptors that bind epinephrine (adrenaline). They are most commonly used for heart conditions and to prevent heart attacks.

Other beta-blockers used for hyperthyroidism include Corgard (nadolol) and  Lopressor (metoprolol). 

With thyroid conditions, beta-blockers do not "treat" hyperthyroidism but rather reduce the body's symptoms of excess thyroid hormone like a fast heart rate, tremors, and anxiety.

Thyroid Cancer Medications

The primary treatment for most thyroid cancers is surgical thyroid removal. Sometimes removal involves the entire thyroid gland (total thyroidectomy) or just a lobe of the thyroid gland (lobectomy).

After surgery, you will require thyroid hormone replacement medication (levothyroxine) to replace thyroid hormone production and suppress tumor regrowth. Other medications used to treat thyroid cancer include chemotherapy, radioactive-iodine therapy, and tyrosine kinase inhibitors.

Thyroid Cancer Medication Names
 Brand Name  Generic Name
 Caprelsa  vandetanib
 Cometriq  cabozantinib-S-malate
 Gavreto  pralsetinib
 Lenvima  lenvatinib mesylate
 Levothyroid  levothyroxine
 Levoxyl  levothyroxine  
 Mekinist  trametinib dimethyl sulfoxide
 Nexavar  sorafenib tosylate
 Radioactive iodine  iodine 131 (I-131)
 Retevmo selpercatinib 
 Synthroid   levothyroxine
 Tafinlar  dabrafenib mesylate
 Tirosint  levothyroxine
 Unithroid  levothyroxine

Levothyroxine

Levothyroxine after thyroid removal is used just as it is for other cases of underactive thyroid. Depending on the extent of the disease and your risk for recurrent thyroid cancer, a healthcare provider will determine what range TSH should be suppressed and adjust the levothyroxine accordingly.

Suppression of the TSH is important for preventing the cancer from returning.

Radioactive-Iodine Therapy

Sometimes radioactive-iodine therapy may be given after surgery. Circumstances in which it may be indicated include:

  • Large thyroid cancers
  • Thyroid cancer that has spread to the lymph nodes
  • High risk for recurrent cancer
  • Patients with Grave's disease who don't want to take methimazole or PTU

Radioactive iodine is given in a hospital setting in either liquid form or as a capsule. Its main goal is to kill off cancer cells after surgery and destroy any remaining thyroid tissue.

Chemotherapy

Chemotherapy, which works by killing rapidly dividing cancer cells, is only given for rare types of thyroid cancer, including medullary, lymphoma, and anaplastic.

Targeted Therapies

Scientists have developed several "targeted therapies"—drugs that target specific markers on cancer cells. Some of these drugs treat advanced or resistant thyroid cancer.

Targeted therapies called kinase inhibitors and tyrosine kinase inhibitors are used for treating thyroid cancer. These medications include:

  • Caprelsa (vandetanib)
  • Cometriq (cabozantinib-S-malate)
  • Gavreto (pralsetinib)
  • Lenvima (lenvatinib mesylate)
  • Mekinist (trametinib dimethyl sulfoxide)
  • Nexavar (sorafenib tosylate)
  • Retevmo (selpercatinib)
  • Tafinlar (dabrafenib mesylate)

These medications partially block thyroid cancers from growing and making new blood vessels.

Summary

The right thyroid medication for you depends on your diagnosis.

Underactive thyroid (hypothyroidism) is treated with thyroid hormone replacement therapy, often a synthetic form of T4, T3, or a combination of T4/T3.

Overactive thyroid (hyperthyroidism) is treated with anti-thyroid medications that inhibit the thyroid from using iodine. In addition, beta-blockers are sometimes prescribed to minimize hyperthyroid symptoms, like a fast heart rate.

Thyroid cancers usually require surgical thyroid removal. Afterward, treatment may involve levothyroxine, radioactive iodine therapy, or targeted therapies.

A Word From Verywell

No doubt, being diagnosed with a thyroid condition can be overwhelming. But by gaining knowledge about the medications used to treat your disease, you are already taking the first step in your care.

Keep in mind that as you continue on your thyroid journey, you are not alone—and most of the time, thyroid conditions are managed well. Don't hesitate to update your healthcare provider on how you are feeling. There are many cases in which a person might benefit from an adjusted dose or even a drug change.

Thyroid Disease Healthcare Provider Discussion Guide

Get our printable guide for your next healthcare provider's appointment to help you ask the right questions.

Doctor Discussion Guide Woman
9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Jonklaas J, Bianco AC, Bauer AJ, et al. Guidelines for the treatment of hypothyroidism: prepared by the American Thyroid Association Task Force on Thyroid Hormone Replacement. Thyroid. 2014;24(12):1670-751. doi:10.1089/thy.2014.0028

  2. U.S. Department of Health and Human Services, National Institute of Diabetes, and Digestive and Kidney Diseases. Hypothyroidism (Underactive Thyroid).

  3. Cleveland Clinic. Thyroiditis: management and treatment.

  4. Ross DS, Burch HB, Cooper DS, et al. 2016 American Thyroid Association guidelines for diagnosis and management of hyperthyroidism and other causes of thyrotoxicosis. Thyroid. 2016;26(10):1343-1421. doi:10.1089/thy.2016.0229.

  5. Burch HB, Cooper DS. Anniversary review. Antithyroid drug therapy: 70 years later. Eur J Endocrinol. 2018;179(5):R261-R274. doi:10.1530/EJE-18-0678

  6. Nguyen QT, Lee EJ, Huang MG, Park YI, Khullar A, Plodkowski RA. Diagnosis and treatment of patients with thyroid cancer. Am Health Drug Benefits. 2015;8(1):30-40.

  7. Saini S, Tulla K, Maker AV, Burman KD, Prabhakar BS. Therapeutic advances in anaplastic thyroid cancer: a current perspective. Mol Cancer. 2018;17(1):154. doi:10.1186/s12943-018-0903-0

  8. National Cancer Institute. Drugs approved for thyroid cancer.

  9. Lorusso L, Pieruzzi L, Biagini A, et al. Lenvatinib and other tyrosine kinase inhibitors for the treatment of radioiodine refractory, advanced, and progressive thyroid cancer. Onco Targets Ther. 2016;9:6467-6477. doi:10.2147/OTT.S84625

Additional Reading

By Mary Shomon
Mary Shomon is a writer and hormonal health and thyroid advocate. She is the author of "The Thyroid Diet Revolution."