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Hyperthyroidism

What is hyperthyroidism?

Hyperthyroidism means your thyroid gland is too active. This tiny gland is found in your neck. An overactive thyroid gland makes too much thyroid hormone. This makes your metabolism work at a faster rate.

What causes hyperthyroidism?

Hyperthyroidism has several causes. These may include:

Graves' disease. This is an autoimmune disorder. It is the most common cause of hyperthyroidism. It happens when an antibody overstimulates the thyroid. This condition is most often found in young to middle-aged women. It also tends to run in families.

Toxic nodular goiter. This condition happens when one or more lumps (nodules) of the thyroid gland become too active. Health experts don't know what causes this to happen. In most cases, the nodules are not cancer (benign). But in rare cases the overactive thyroid tissue is cancer.

Thyroiditis. This occurs when the thyroid becomes irritated. It temporarily causes the thyroid to be overactive. The thyroid then often becomes underactive.

Having too much iodine in your diet or in medicines, such as amiodarone

Having a noncancer tumor in the pituitary gland that makes your thyroid overactive

Who is at risk for hyperthyroidism?

These things may make it more likely for you to have hyperthyroidism:

You are a woman

You are older than age 60

You have had thyroid problems in the past

Your family has a history of thyroid problems

You have certain conditions, such as type 1 diabetes

You consume too much iodine. This can happen if you eat a lot of iodine-rich foods or take too much medicine that has this chemical.

You are pregnant or have had a baby in the last 6 months

What are the symptoms of hyperthyroidism?

Symptoms are different for each person. Here are the most common ones:

Nervousness

Irritability

Sweating more than normal

Thinning of the skin

Fine, brittle hair

Weak muscles, especially in the upper arms and thighs

Shaky hands

Fast heartbeat (palpitations)

High blood pressure

More bowel movements than normal, diarrhea

Weight loss

Trouble dealing with the heat

Problems sleeping

Prominent eyes

Sensitivity to bright light

Confusion

Irregular menstrual cycle in women

Tiredness and lack of energy (fatigue)

Larger than normal thyroid gland (goiter)

These symptoms may look like other health problems. Always see your healthcare provider for a diagnosis.

How is hyperthyroidism diagnosed?

Your healthcare provider will ask about your health history. You will also need a physical exam. Other tests that can help diagnose hyperthyroidism include:

Blood tests. They can measure the amount of thyroid hormone and thyroid stimulating hormone in your blood.

Thyroid ultrasound. This test can see if your thyroid gland has any nodules.

Thyroid scan. This test uses a radioactive substance to make an image of the thyroid.

How is hyperthyroidism treated?

Treatment will depend on your child’s symptoms, age, and general health. It will also depend on how severe the condition is.

Treatment may include:

Medicine. It can help lower the level of thyroid hormones in the blood.

Radioactive iodine. It comes in the form of a pill or liquid. It slowly destroys the cells of the thyroid gland so that less thyroid hormone is made.

Surgery. You may need to have all or part of your thyroid removed.

Beta blockers. These medicines block the action of the thyroid hormone on the body. That helps with rapid heart rate and palpitations.

What are possible complications of hyperthyroidism?

If your hyperthyroidism is not treated, these complications may happen:

Thyroid crisis, when symptoms get worse because of stress or illness

Heart problems, such as an abnormal rhythm or heart failure

Weak, brittle bones (osteoporosis)

Pregnancy problems, such as miscarriage, early delivery, and preeclampsia or high blood pressure

When should I call my healthcare provider?

Tell your healthcare provider if your symptoms get worse or you have new symptoms. If you are a woman of childbearing age and want to become pregnant, talk with your provider first.

Key points about hyperthyroidism

Hyperthyroidism means your thyroid gland is too active. This tiny gland is found in your neck. If it is overactive, it makes too much thyroid hormone. Your body’s metabolism then begins to work at a faster rate.

This condition can be caused by Graves' disease, toxic nodular goiter, thyroiditis, and taking too much thyroid medicine.