Hyperthyroidism (overactive thyroid)
Hyperthyroidism (overactive thyroid)
Hyperthyroidism (overactive thyroid) is a condition in which your thyroid gland produces too much of the hormone thyroxine. Hyperthyroidism can accelerate your body's metabolism significantly, causing sudden weight loss, a rapid or irregular heartbeat, sweating, and nervousness or irritability.
Several treatment options are available if you have hyperthyroidism. Doctors use anti-thyroid medications and radioactive iodine to slow the production of thyroid hormones. Sometimes, treatment of hyperthyroidism involves surgery to remove all or part of your thyroid gland. Although hyperthyroidism can be serious if you ignore it, most people respond well once hyperthyroidism is diagnosed and treated.
Hyperthyroidism can mimic other health problems, which may make it difficult for your doctor to diagnose. It can also cause a wide variety of signs and symptoms, including:
Older adults are more likely to have either no signs or symptoms or subtle ones, such as an increased heart rate, heat intolerance and a tendency to become tired during ordinary activities. Medications called beta blockers, which are used to treat high blood pressure and other conditions, can mask many of the signs of hyperthyroidism.
Signs and symptoms of Graves' ophthalmopathy include:
When to see a doctor
If you've been treated for hyperthyroidism or currently are being treated, see your doctor regularly as advised so that he or she can monitor your condition.
A number of conditions, including Graves' disease, toxic adenoma, Plummer's disease (toxic multinodular goiter) and thyroiditis, can cause hyperthyroidism.
Your thyroid is a butterfly-shaped gland situated at the base of your neck, just below your Adam's apple. Although it weighs less than an ounce, the thyroid gland has an enormous impact on your health. Every aspect of your metabolism is regulated by thyroid hormones.
Your thyroid gland produces two main hormones, thyroxine (T-4) and triiodothyronine (T-3), that influence every cell in your body. They maintain the rate at which your body uses fats and carbohydrates, help control your body temperature, influence your heart rate, and help regulate the production of protein. Your thyroid also produces calcitonin, a hormone that helps regulate the amount of calcium in your blood.
How it all works
The hypothalamus signals your pituitary gland to make a hormone called thyroid-stimulating hormone (TSH). Your pituitary gland then releases TSH — the amount depends on how much T-4 and T-3 are in your blood. If you don't have enough T-4 and T-3 in your blood, your TSH will rise; if you have too much, your TSH level will fall. Finally, your thyroid gland regulates its production of hormones based on the amount of TSH it receives. If the thyroid gland is diseased and is releasing too much thyroid hormone on its own, the TSH blood level will remain below normal; if the diseased thyroid gland cannot make enough thyroid hormone, the TSH blood level will remain high.
Reasons for too much thyroxine (T-4)
Your thyroid gland is located at the base of your neck, just below the Adam's apple. ...
Hyperthyroidism, particularly Graves' disease, tends to run in families and is more common in women than in men. If another member of your family has a thyroid condition, talk with your doctor about what this may mean for your health and whether he or she has any recommendations for monitoring your thyroid function.
Hyperthyroidism can lead to a number of complications:
Preparing for your appointment
You're likely to start by seeing your family doctor or a general practitioner. However, in some cases, you may be referred immediately to a doctor who specializes in the body's hormone-secreting glands (endocrinologist). If you have eye involvement, you may also be referred to an eye doctor (ophthalmologist).
It's good to prepare for your appointment. Here's some information to help you get ready for your appointment, and to know what to expect from your doctor.
What you can do
Preparing a list of questions will help you make the most of your time with your doctor. For hyperthyroidism, some basic questions to ask your doctor include:
Don't hesitate to ask any other relevant questions you have.
What to expect from your doctor
Tests and diagnosis
Hyperthyroidism is diagnosed using:
If blood tests indicate hyperthyroidism, your doctor may recommend one of the following tests to help determine why your thyroid is overactive:
Treatments and drugs
Several treatments for hyperthyroidism exist. The best approach for you depends on your age, physical condition and the severity of your disorder:
In a thyroidectomy, your doctor removes most of your thyroid gland. Risks of this surgery include damage to your vocal cords and parathyroid glands — four tiny glands situated on the back of your thyroid gland that help control the level of calcium in your blood. In addition, you'll need lifelong treatment with levothyroxine (Levoxyl, Synthroid, others) to supply your body with normal amounts of thyroid hormone. If your parathyroid glands also are removed, you'll need medication to keep your blood-calcium levels normal.
Lifestyle and home remedies
Once you begin treatment, symptoms of hyperthyroidism should subside and you should start feeling much better. The following suggestions also may help:
Coping and support
If you've been diagnosed with hyperthyroidism, the most important thing is to receive the necessary medical care. After you and your doctor have decided on a course of action, there are some things you can do that will help you cope with the condition and support your body during its healing process.
Last Updated: 2012-11-20
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