underactive

What is hypothyroidism?

Hypothyroidism, or underactive thyroid, happens when your thyroid gland doesn't make enough thyroid hormones to meet your body's needs.

Your thyroid is a small, butterfly-shaped gland in the front of your neck. It makes hormones that control the way the body uses energy. These hormones affect nearly every organ in your body and control many of your body's most important functions. For example, they affect your breathing, heart rate, weight, digestion, and moods. Without enough thyroid hormones, many of your body's functions slow down. But there are treatments that can help.

What causes hypothyroidism?

Hypothyroidism has several causes. They include:

• Hashimoto's disease, an autoimmune disorder where your immune system attacks your thyroid. This is the most common cause.
• Thyroiditis, inflammation of the thyroid
• Congenital hypothyroidism, hypothyroidism that is present at birth
• Surgical removal of part or all of the thyroid
• Radiation treatment of the thyroid
• Certain medicines
• In rare cases, a pituitary disease or too much or too little iodine in your diet

Who is at risk for hypothyroidism?

You are at higher risk for hypothyroidism if you:

• Are a woman
• Are older than age 60
• Have had a thyroid problem before, such as a goiter
• Have had surgery to correct a thyroid problem
• Have received radiation treatment to the thyroid, neck, or chest
• Have a family history of thyroid disease
• Were pregnant or had a baby in the past 6 months
• Have Turner syndrome, a genetic disorder that affects females
• Have pernicious anemia, in which the body cannot make enough healthy red blood cells because it does not have enough vitamin B12
• Have Sjogren's syndrome, a disease that causes dry eyes and mouth
• Have type 1 diabetes
• Have rheumatoid arthritis, an autoimmune disease that affects the joints
• Have lupus, a chronic autoimmune disease

What are the symptoms of hypothyroidism?

The symptoms of hypothyroidism can vary from person to person and may include:

• Fatigue
• Weight gain
• A puffy face
• Trouble tolerating cold
• Joint and muscle pain
• Constipation
• Dry skin
• Dry, thinning hair
• Decreased sweating
• Heavy or irregular menstrual periods
• Fertility problems in women
• Depression
• Slowed heart rate
• Goiter, an enlarged thyroid that may cause your neck to look swollen. Sometimes it can cause trouble with breathing or swallowing.

Because hypothyroidism develops slowly, many people don't notice symptoms of the disease for months or even years.

What other problems can hypothyroidism cause?

Hypothyroidism can contribute to high cholesterol. In rare cases, untreated hypothyroidism can cause myxedema coma. This is a condition in which your body's functions slow down to the point that it becomes life-threatening.

During pregnancy, hypothyroidism can cause complications, such as premature birth, high blood pressure in pregnancy, and miscarriage. It can also slow the baby's growth and development.

How is hypothyroidism diagnosed?

Your health care provider may use many tools to make a diagnosis:

• A medical history, including asking about your symptoms
• A physical exam
• Thyroid tests, such as
  • TSH, T3, T4, and thyroid antibody blood tests
  • Imaging tests, such as a thyroid scan, ultrasound, or radioactive iodine uptake test. A radioactive iodine uptake test measures how much radioactive iodine your thyroid takes up from your blood after you swallow a small amount of it.

What are the treatments for hypothyroidism?

The treatment for hypothyroidism is medicine to replace the hormone that your own thyroid can no longer make. About 6 to 8 weeks after you start taking the medicine, you will get a blood test to check your thyroid hormone level. Your health care provider will adjust your dose if needed. Each time your dose is adjusted, you'll have another blood test. Once you find the right dose, you will probably get a blood test in 6 months. After that, you will need the test once a year.

If you take your medicine according to the instructions, you usually should be able to control the hypothyroidism. You should never stop taking your medicine without talking with your health care provider first.

If you have Hashimoto's disease or other types of autoimmune thyroid disorders, you may be sensitive to harmful side effects from iodine. Talk to your health care provider about which foods, supplements, and medicines you need to avoid.

Women need more iodine when they are pregnant because the baby gets iodine from the mother's diet. If you are pregnant, talk with your health care provider about how much iodine you need.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

What is carpal tunnel syndrome?

Carpal tunnel syndrome is the name for a group of problems that includes numbness, tingling, weakness, or pain in your wrist or hand. It's a very common condition that happens when a nerve in your wrist becomes squeezed.

The carpal tunnel is a narrow opening between the bones in your wrist and the ligament that holds them together. A nerve, called the median nerve, runs from your lower arm through the carpal tunnel and into your hand. This nerve provides feeling to your thumb and first three fingers. It also helps you move your thumb.

Tendons also run from your lower arm, through the carpal tunnel, and into your hand. The tendons connect your finger bones to muscles in your arm, so you can bend your fingers.

If the tendons become swollen or irritated inside the carpal tunnel, they may press on the nerve. The squeezed nerve may not work well, which can lead to numbness, weakness, and other symptoms of carpal tunnel syndrome.

What causes carpal tunnel syndrome?

In certain cases, the cause of carpal tunnel syndrome is unknown. But it usually happens from a combination of things that affect the structures in your wrist, such as:

• Injury to your wrist that causes swelling, such as a sprain or broken bone
• Health conditions that can affect your nerves, joints, or other parts of your wrist, for example:
  • Diabetes.
  • Rheumatoid arthritis.
  • A cyst or tumor in your wrist.
  • Changes in certain hormones, which may cause swelling from extra fluid in your body. Examples include an underactive thyroid gland (hypothyroidism), pregnancy and menopause.
  • Problems with the way your wrist is formed.
• Doing the same wrist and hand movements over and over, such as:
  • Assembly line work.
  • Carpentry or using tools that vibrate.
  • Knitting, gardening, or sports, such as golf.

Researchers aren't sure whether long-term typing or computer use leads to carpal tunnel syndrome.

Who is more likely to develop carpal tunnel syndrome?

Carpal tunnel syndrome usually happens only in adults. You're more likely to develop it if you:

• Are a woman. Women are three times more likely to have carpal tunnel syndrome than men.
• Have a health condition that may affect structures in your wrist.
• Do activities with repeated hand motions.
• Have had a wrist injury.
• Have a close relative who has had carpal tunnel syndrome, such as a parent, brother or sister.

What are the symptoms of carpal tunnel syndrome?

You may feel numbness, tingling or burning in your fingers, especially in your thumb, index, and middle fingers. Symptoms often affect both hands.

In the early stages, symptoms usually:

• Start slowly in your dominant hand (the one you write with)
• Happen at night if you sleep with your wrists bent

As symptoms get worse, you may notice:

• Tingling, pain, or weakness with certain activities, such as driving or holding a phone
• Difficulty grasping or holding small things
• Feeling like your fingers are swollen when they're not

Without treatment, you could lose feeling in some fingers and have permanent weakness in your thumb. But early diagnosis and treatment can help prevent lasting damage.

How is carpal tunnel syndrome diagnosed?

To find out if you have carpal tunnel syndrome, your health care provider will:

• Ask about your medical history
• Ask about your family health history
• Do a physical exam
• Order tests if needed, such as:
  • Lab tests to look for diseases that may damage nerves
  • X-rays to look for broken bones or arthritis
  • Tests to measure the electrical activity in your nerves and muscles
  • Ultrasound to check the nerve in the carpal tunnel

What are the treatments for carpal tunnel syndrome?

It's easier to treat carpal tunnel syndrome early on, so you should start treatment as soon as possible. Your provider will first treat any health conditions you have that may cause your symptoms. The next step would be treatments for carpal tunnel syndrome. They may include:

• Wrist splints (usually worn at night).
• Rest.
• Medicines to reduce swelling and pain:
• Over-the-counter pain relievers, such as aspirin, ibuprofen, and naproxen sodium.
• Prescriptionsteroids, either pills or an injection (shot) into your wrist.
• Other therapies (complementary and integrative medicine). Research shows that yoga may help with pain and weakness. Some people may find acupuncture and chiropractic care helpful, but research hasn't shown that these therapies can improve carpal tunnel syndrome. If you want to try other therapies, talk with your provider first.
• Surgery to make more space in the carpal tunnel. Surgery may be an option if your symptoms are severe and other treatments don't work. It involves cutting the wrist ligament to take pressure off the nerve. Recovery may take months. Carpal tunnel syndrome rarely comes back after surgery, but mild symptoms may last.

Can carpal tunnel syndrome be prevented?

You may help prevent carpal tunnel syndrome if you protect your wrists:

• Use good posture to keep your wrists in a natural position.
• Keep your hands warm to keep your muscles flexible. Fingerless gloves may help.
• Take work breaks and vary your tasks.
• Stretch and exercise your hands and wrists.
• Organize your workspace and tools to reduce strain on your hands and wrists.

What is hyperthyroidism?

Hyperthyroidism, or overactive thyroid, happens when your thyroid gland makes more thyroid hormones than your body needs.

Your thyroid is a small, butterfly-shaped gland in the front of your neck. It makes hormones that control the way the body uses energy. These hormones affect nearly every organ in your body and control many of your body's most important functions. For example, they affect your breathing, heart rate, weight, digestion, and moods. If not treated, hyperthyroidism can cause serious problems with your heart, bones, muscles, menstrual cycle, and fertility. But there are treatments that can help.

What causes hyperthyroidism?

Hyperthyroidism has several causes. They include:

• Graves' disease, an autoimmune disorder in which your immune system attacks your thyroid and causes it to make too much hormone. This is the most common cause.
• Thyroid nodules, which are growths on your thyroid. They are usually benign (not cancer). But they may become overactive and make too much thyroid hormone. Thyroid nodules are more common in older adults.
• Thyroiditis, inflammation of the thyroid. It causes stored thyroid hormone to leak out of your thyroid gland.
• Too much iodine. Iodine is found in some medicines, cough syrups, seaweed and seaweed-based supplements. Taking too much of them can cause your thyroid to make too much thyroid hormone.
• Too much thyroid medicine. This can happen if people who take thyroid hormone medicine for hypothyroidism (underactive thyroid) take too much of it.

Who is at risk for hyperthyroidism?

You are at higher risk for hyperthyroidism if you:

• Are a woman
• Are older than age 60
• Have been pregnant or had a baby within the past 6 months
• Have had thyroid surgery or a thyroid problem, such as goiter
• Have a family history of thyroid disease
• Have pernicious anemia, in which the body cannot make enough healthy red blood cells because it does not have enough vitamin B12
• Have type 1 diabetes or primary adrenal insufficiency, a hormonal disorder
• Get too much iodine, from eating large amounts of foods containing iodine or using iodine-containing medicines or supplements

What are the symptoms of hyperthyroidism?

The symptoms of hyperthyroidism can vary from person to person and may include:

• Nervousness or irritability
• Fatigue
• Muscle weakness
• Trouble tolerating heat
• Trouble sleeping
• Tremor, usually in your hands
• Rapid and irregular heartbeat
• Frequent bowel movements or diarrhea
• Weight loss
• Mood swings
• Goiter, an enlarged thyroid that may cause your neck to look swollen. Sometimes it can cause trouble with breathing or swallowing.

Adults over age 60 may have different symptoms than younger adults. For example, they may lose their appetite or withdraw from other people. Sometimes this can be mistaken for depression or dementia.

What other problems can hyperthyroidism cause?

If hyperthyroidism isn't treated, it can cause some serious health problems, including:

• An irregular heartbeat that can lead to blood clots, stroke, heart failure, and other heart problems
• An eye disease called Graves' ophthalmopathy. It can cause double vision, light sensitivity, and eye pain. In rare cases, it can lead to vision loss.
• Thinning bones and osteoporosis
• Fertility problems in women
• Complications in pregnancy, such as premature birth, low birth weight, high blood pressure in pregnancy, and miscarriage

How is hyperthyroidism diagnosed?

Your health care provider may use many tools to make a diagnosis:

• A medical history, including asking about symptoms
• A physical exam
• Thyroid tests, such as
  • TSH, T3, T4, and thyroid antibody blood tests
  • Imaging tests, such as a thyroid scan, ultrasound, or radioactive iodine uptake test. A radioactive iodine uptake test measures how much radioactive iodine your thyroid takes up from your blood after you swallow a small amount of it.

What are the treatments for hyperthyroidism?

The treatments for hyperthyroidism include medicines, radioiodine therapy, and thyroid surgery:

• Medicines for hyperthyroidism include
  • Antithyroid medicines, which cause your thyroid to make less thyroid hormone. You probably need to take the medicines for 1 to 2 years. In some cases, you might need to take the medicines for several years. This is the simplest treatment, but it is often not a permanent cure.
  • Beta blocker medicines, which can reduce symptoms such as tremors, rapid heartbeat, and nervousness. They work quickly and can help you feel better until other treatments take effect.
• Radioiodine therapy is a common and effective treatment for hyperthyroidism. It involves taking radioactive iodine by mouth as a capsule or liquid. This slowly destroys the cells of the thyroid gland that produce thyroid hormone. It does not affect other body tissues. Almost everyone who has radioactive iodine treatment later develops hypothyroidism. This is because the thyroid hormone-producing cells have been destroyed. But hypothyroidism is easier to treat and causes fewer long-term health problems than hyperthyroidism.
• Surgery to remove part or most of the thyroid gland is done in rare cases. It might be an option for people with large goiters or pregnant women who cannot take antithyroid medicines. If you have all of your thyroid removed, you will need to take thyroid medicines for the rest of your life. Some people who have part of their thyroid removed also need to take medicines.

If you have hyperthyroidism, it's important not to get too much iodine. Talk to your health care provider about which foods, supplements, and medicines you need to avoid.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases