Your thyroid is a gland below the Adam’s apple in the front of your neck.
Your thyroid releases thyroid hormones. The hormones control how fast your body’s chemical functions work (metabolic rate). Almost every cell in your body needs thyroid hormones. Among many other things, thyroid hormones help control:
How fast you burn calories
How fast your heart beats
Your body temperature
Locating the Thyroid Gland
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What is hyperthyroidism?
Hyperthyroidism is when your thyroid is too active and makes more thyroid hormone than your body needs.
Symptoms include a fast heart rate, high blood pressure, and weight loss
Blood tests can confirm you have hyperthyroidism
Medicines can usually help with hyperthyroidism
Hyperthyroidism happens in about 1 out of every 100 people
Thyroid storm is very severe hyperthyroidism that happens when your thyroid suddenly releases a dangerous amount of hormones. It's usually brought on by an infection, heart attack, stroke, surgery, or extreme stress. It's an emergency that can be fatal if not treated quickly.
What causes hyperthyroidism?
The most common causes include:
Graves disease
Thyroid inflammation (thyroiditis)
Growths (nodules) in your thyroid
Certain medicines
In Graves disease, your body's immune system Overview of the Immune System The immune system is your body's defense system. It helps protect you from illness and infection. The immune system's job is to attack things that don’t belong in your body, including: Germs... read more mistakenly attacks the thyroid (an autoimmune disease Autoimmune Diseases The immune system is your body's defense system. It helps protect you from illness and infection. The immune system usually attacks invading bacteria, viruses, and cancer cells. With an autoimmune... read more ). Most autoimmune diseases make things stop working. But in Graves disease, the attack by your immune system makes your thyroid work harder and make more thyroid hormones.
Thyroiditis results from certain viral infections and other diseases that inflame your thyroid. Damaged cells in the inflamed thyroid can release extra thyroid hormones.
Thyroid nodules are small growths that often result from a genetic disease. Some nodules release thyroid hormones. Thyroid cancers Thyroid Cancer Your thyroid is a gland below the Adam’s apple in your neck. Your thyroid releases thyroid hormones. The hormones control how fast your body’s chemical functions work (metabolic rate). Almost... read more also are small growths, but they rarely produce thyroid hormones.
What are the symptoms of hyperthyroidism?
Symptoms of hyperthyroidism usually involve a speeding up of body functions. So you might have:
High blood pressure
A lot of sweating and a feeling of being very warm all the time
Shaky hands
Nervousness, anxiety, and difficulty sleeping
Weight loss
Frequent bowel movements, sometimes with diarrhea
In women, irregular or no menstrual periods
Some diseases that cause hyperthyroidism make your thyroid swell or hurt.
Older people with hyperthyroidism may have less obvious symptoms. Symptoms in older people may include:
Weakness
Confusion
Weight loss
Depression
People with Graves disease can have problems with their eyes including:
Eyes that bulge
Red eyes
Dry eyes
Sometimes, blurry vision or seeing double
Thyroid storm
Symptoms of thyroid storm are the same as those of regular hyperthyroidism but more severe, including:
High fever
Extreme weakness
Restlessness and confusion
Passing out
Shock (a dangerous drop in blood pressure)
How can doctors tell if I have hyperthyroidism?
Doctors will do:
Thyroid function tests Overview of the Thyroid Gland Your thyroid is a gland below the Adam’s apple in the front of your neck. Glands make and release hormones. Hormones stimulate other cells or tissues into action. The thyroid makes thyroid hormones... read more , including blood tests and imaging tests of your thyroid gland
How do doctors treat hyperthyroidism?
Treatment depends on the cause of the hyperthyroidism.
Doctors will treat you with:
Medicines, such as beta blockers, to control symptoms
Medicines to keep your thyroid from making thyroid hormones
Sometimes, doctors need to permanently stop your thyroid from making any more hormones. They may stop your thyroid by:
Doing surgery to remove part or all of your thyroid
Giving you high doses of radioactive iodine, which will destroy the thyroid
After you've had surgery or radioactive iodine treatments, you'll need to take thyroid hormone pills because your body no longer makes its own thyroid hormones.