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
- 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
Metabolism is the process your body uses to get or make energy from the food you eat. Food is made up of proteins, carbohydrates, and fats. Chemicals in your digestive system break the food parts down into sugars and acids, your body's fuel. Your body can use this fuel right away, or it can store the energy in your body tissues, such as your liver, muscles, and body fat.
A metabolic disorder occurs when abnormal chemical reactions in your body disrupt this process. When this happens, you might have too much of some substances or too little of other ones that you need to stay healthy. There are different groups of disorders. Some affect the breakdown of amino acids, carbohydrates, or lipids. Another group, mitochondrial diseases, affects the parts of the cells that produce the energy.
You can develop a metabolic disorder when some organs, such as your liver or pancreas, become diseased or do not function normally. Diabetes is an example.
Your muscles help you move and help your body work. Different types of muscles have different jobs. There are many problems that can affect muscles. Muscle disorders can cause weakness, pain or even paralysis.
Causes of muscle disorders include:
- Injury or overuse, such as sprains or strains, cramps or tendinitis
- A genetic disorder, such as muscular dystrophy
- Some cancers
- Inflammation, such as myositis
- Diseases of nerves that affect muscles
- Certain medicines
Sometimes the cause of muscle disorders is unknown.
The brain, spinal cord, and nerves make up the nervous system. Together they control all the workings of the body. When something goes wrong with a part of your nervous system, you can have trouble moving, speaking, swallowing, breathing, or learning. You can also have problems with your memory, senses, or mood.
There are more than 600 neurologic diseases. Major types include:
- Diseases caused by faulty genes, such as Huntington's disease and muscular dystrophy
- Problems with the way the nervous system develops, such as spina bifida
- Degenerative diseases, where nerve cells are damaged or die, such as Parkinson's disease and Alzheimer's disease
- Diseases of the blood vessels that supply the brain, such as stroke
- Injuries to the spinal cord and brain
- Seizure disorders, such as epilepsy
- Cancer, such as brain tumors
- infections, such as meningitis
A nursing home is a place for people who don't need to be in a hospital but can't be cared for at home. Most nursing homes have nursing aides and skilled nurses on hand 24 hours a day.
Some nursing homes are set up like a hospital. The staff provides medical care, as well as physical, speech and occupational therapy. There might be a nurses' station on each floor. Other nursing homes try to be more like home. They try to have a neighborhood feel. Often, they don't have a fixed day-to-day schedule, and kitchens might be open to residents. Staff members are encouraged to develop relationships with residents.
Some nursing homes have special care units for people with serious memory problems such as Alzheimer's disease. Some will let couples live together. Nursing homes are not only for older adults, but for anyone who requires 24-hour care.
NIH: National Institute on Aging