Understand what happens when your thyroid is overactive and learn about treatment for this condition.
Hyperthyroidism happens when the thyroid gland makes too much thyroid hormone. This condition also is called overactive thyroid. Hyperthyroidism speeds up the body's metabolism. That can cause many symptoms, such as weight loss, hand tremors, and rapid or irregular heartbeat.
Several treatments are available for hyperthyroidism. Anti-thyroid medicines and radioiodine can be used to slow the amount of hormones the thyroid gland makes. Sometimes, hyperthyroidism treatment includes surgery to remove all or part of the thyroid gland. In some cases, depending on what's causing it, hyperthyroidism may improve without medication or other treatment.
Hyperthyroidism sometimes looks like other health problems. That can make it hard to diagnose. It can cause many symptoms, including:
Older adults are more likely to have symptoms that are hard to notice. These symptoms may include an irregular heartbeat, weight loss, depression, and feeling weak or tired during ordinary activities.
If you lose weight without trying, or if you notice a rapid heartbeat, unusual sweating, swelling at the base of your neck or other symptoms of hyperthyroidism, make an appointment with your health care provider. Tell your provider about all the symptoms you've noticed even if they are minor.
After a diagnosis of hyperthyroidism, most people need regular follow-up visits with their health care provider to monitor the condition.
Hyperthyroidism can be caused by several medical conditions that affect the thyroid gland. The thyroid is a small, butterfly-shaped gland at the base of the neck. It has a big impact on the body. Every part of metabolism is controlled by hormones that the thyroid gland makes.
The thyroid gland produces two main hormones: thyroxine (T-4) and triiodothyronine (T-3). These hormones affect every cell in the body. They support the rate at which the body uses fats and carbohydrates. They help control body temperature. They have an effect on heart rate. And they help control how much protein the body makes.
Hyperthyroidism happens when the thyroid gland puts too much of those thyroid hormones into the bloodstream. Conditions that can lead to hyperthyroidism include:
The thyroid gland is located at the base of the neck, just below the Adam's apple.
Risk factors for hyperthyroidism include:
Hyperthyroidism can lead to the following complications.
Some of the most serious complications of hyperthyroidism involve the heart, including:
Untreated hyperthyroidism can lead to weak, brittle bones. This condition is called osteoporosis. The strength of bones depends, in part, on the amount of calcium and other minerals in them. Too much thyroid hormone makes it hard for the body to get calcium into bones.
Some people with hyperthyroidism develop a problem called thyroid eye disease. It's more common in people who smoke. This disorder affects the muscles and other tissues around the eyes.
Symptoms of thyroid eye disease include:
Eye problems that go untreated may cause vision loss.
In rare cases, people with Graves' disease develop Graves' dermopathy. This causes the skin to change colors and swell, often on the shins and feet.
This rare condition also is called thyroid storm. Hyperthyroidism raises the risk of thyrotoxic crisis. It causes severe, sometimes life-threatening symptoms. It requires emergency medical care. Symptoms may include:
Hyperthyroidism is diagnosed with a medical history, physical exam and blood tests. Depending on the results of the blood tests, you may need other tests too.
Medical history and physical exam. During the exam, your health care provider may check for:
Your provider also examines your thyroid gland as you swallow to see if it's larger than usual, bumpy or tender.
Blood tests. Blood tests that measure the hormones T-4 and T-3 and thyroid-stimulating hormone (TSH) can confirm a diagnosis of hyperthyroidism. A high level of T-4 and a low level of TSH is common in people with hyperthyroidism.
Blood tests are particularly important for older adults because they may not have classic symptoms of hyperthyroidism.
Thyroid blood tests may give false results if you take biotin. Biotin is a B vitamin supplement that also may be found in multivitamins. Tell your health care provider if you are taking biotin or a multivitamin with biotin. To make sure your blood test is accurate, your health care provider may ask you to stop taking biotin 3 to 5 days before the test.
If blood test results show hyperthyroidism, your health care provider may suggest one of the following tests. They can help find out why your thyroid is overactive.
Radioiodine scan and uptake test. For this test, you take a small, dose of radioactive iodine, called radioiodine, to see how much of it collects in your thyroid gland and where it collects in the gland.
If your thyroid gland takes in a high amount of radioiodine, that means your thyroid gland is making too much thyroid hormone. The most likely cause is either Graves' disease or overactive thyroid nodules.
If your thyroid gland takes in a low amount of radioiodine, that means hormones stored in the thyroid gland are leaking into the bloodstream. In that case, it's likely that you have thyroiditis.
There are several treatments available for hyperthyroidism. The best approach for you depends on your age and health. The underlying cause of hyperthyroidism and how severe it is make a difference too. Your personal preference also should be considered as you and your health care provider decide on a treatment plan. Treatment may include:
Anti-thyroid medicine. These medications slowly ease symptoms of hyperthyroidism by preventing the thyroid gland from making too many hormones. Anti-thyroid medications include methimazole and propylthiouracil. Symptoms usually begin to improve within several weeks to months.
Treatment with anti-thyroid medicine typically lasts 12 to 18 months. After that, the dose may be slowly decreased or stopped if symptoms go away and if blood test results show that thyroid hormone levels have returned to the standard range. For some people, anti-thyroid medicine puts hyperthyroidism into long-term remission. But other people may find that hyperthyroidism comes back after this treatment.
Although rare, serious liver damage can happen with both anti-thyroid medications. But because propylthiouracil has caused many more cases of liver damage, it's generally used only when people can't take methimazole. A small number of people who are allergic to these medicines may develop skin rashes, hives, fever or joint pain. They also can raise the risk of infection.
Thyroidectomy. This is surgery to remove part of or all of the thyroid gland. It is not used often to treat hyperthyroidism. But it may be an option for people who are pregnant. It also may be a choice for those who can't take anti-thyroid medicine and don't want to or can't take radioiodine therapy.
Risks of this surgery include damage to the vocal cords and parathyroid glands. The parathyroid glands are four tiny glands on the back of the thyroid. They help control the level of calcium in the blood.
People who have a thyroidectomy or radioiodine therapy need lifelong treatment with the medicine levothyroxine (Levoxyl, Synthroid, others). It supplies the body with thyroid hormones. If the parathyroid glands are removed during surgery, medicine also is needed to keep blood calcium in a healthy range.
If you have thyroid eye disease, you may be able to manage mild symptoms with self-care steps, such as artificial tear drops and lubricating eye gels. Avoiding wind and bright lights can help too.
More-severe symptoms may need treatment with medicine called corticosteroids, such as methylprednisolone or prednisone. They can lessen swelling behind the eyeballs. The medicine teprotumumab (Tepezza) also may be used to control moderate to severe symptoms. If those medicines don't ease symptoms, other medicines are sometimes used to treat thyroid eye disease. They include, tocilizumab (Actemra), rituximab (Rituxan) and mycophenolate mofetil (Cellcept).
In some cases, surgery may be needed to treat thyroid eye disease, including:
Once you begin treatment, symptoms of hyperthyroidism likely will get better. Along with your treatment, your health care provider might suggest that you reduce iodine in your diet. It can make hyperthyroidism worse. Kelp, dulse and other types of seaweed contain a lot of iodine. Cough syrup and multivitamins also may contain iodine.
If you have Graves' disease that causes eye or skin problems, taking the following steps may help ease symptoms:
If you've been diagnosed with hyperthyroidism, it's important that you get the medical care you need. After you and your health care provider have decided on a treatment plan, there also are some things you can do to cope with the condition and help your body heal.
You'll likely start by seeing your primary care provider. But you may be referred directly to a specialist in hormone disorders, called an endocrinologist. If you have eye problems, you may be referred to an eye doctor, also called an ophthalmologist.
Here's some information to help you get ready for your appointment and to know what to expect from your health care provider.
Writing a list of questions will help you make the most of your time with your health care provider. For hyperthyroidism, some questions to ask include:
Don't hesitate to ask other questions.
Your health care provider is likely to ask you some questions, including: