Hyperthyroidism, also called overactive thyroid, is when the thyroid gland makes more thyroid hormones than your body needs. The thyroid is a small, butterfly-shaped gland in the front of your neck. Thyroid hormones control the way the body uses energy, so they affect nearly every organ in your body, even the way your heart beats.
Possible Causes of Hyperthyroidism:
Hyperthyroidism has several causes, including Graves’ disease, thyroid nodules, and thyroiditis—inflammation of the thyroid. Rarely, hyperthyroidism is caused by a noncancerous tumor of the pituitary gland located at the base of the brain. Consuming too much iodine or taking too much thyroid hormone medicine also may raise your thyroid hormone levels.
Graves’ disease is the most common cause of hyperthyroidism. Graves’ disease is an autoimmune disorder. With this disease, your immune system attacks the thyroid and causes it to make too much thyroid hormone.
-Overactive thyroid nodules
Thyroid nodules are lumps in your thyroid. Thyroid nodules are common and usually benign, meaning they are not cancerous. However, one or more nodules may become overactive and produce too much thyroid hormone. The presence of many overactive nodules occurs most often in older adults.
Thyroiditis is inflammation of your thyroid that causes stored thyroid hormone to leak out of your thyroid gland. The hyperthyroidism may last for up to 3 months, after which your thyroid may become underactive, a condition called hypothyroidism. The hypothyroidism usually lasts 12 to 18 months, but sometimes is permanent.
Several types of thyroiditis can cause hyperthyroidism and then cause hypothyroidism:
- Subacute thyroiditis. This condition involves a painfully inflamed and enlarged thyroid. Experts are not sure what causes subacute thyroiditis, but it may be related to an infection caused by a virus or bacteria.
- Postpartum thyroiditis. This type of thyroiditis develops after a woman gives birth.
- Silent thyroiditis. This type of thyroiditis is called “silent” because it is painless, even though your thyroid may be enlarged. Experts think silent thyroiditis is probably an autoimmune condition.
-Too much iodine
Your thyroid uses iodine to make thyroid hormone. The amount of iodine you consume affects the amount of thyroid hormone your thyroid makes. In some people, consuming large amounts of iodine may cause the thyroid to make too much thyroid hormone.
Some medicines and cough syrups may contain a lot of iodine. One example is the heart medicine amiodarone. Seaweed and seaweed-based supplements also contain a lot of iodine.
-Too much thyroid hormone medicine:
Some people who take thyroid hormone medicine for hypothyroidism may take too much. If you take thyroid hormone medicine, you should see your doctor at least once a year to have your thyroid hormone levels checked. You may need to adjust your dose if your thyroid hormone level is too high.
Some other medicines may also interact with thyroid hormone medicine to raise hormone levels. If you take thyroid hormone medicine, ask your doctor about interactions when starting new medicines.
How do doctors diagnose hyperthyroidism?
Your doctor will take a medical history and do a physical exam, but also will need to do some tests to confirm a diagnosis of hyperthyroidism. Many symptoms of hyperthyroidism are the same as those of other diseases, so doctors usually can’t diagnose hyperthyroidism based on symptoms alone.
Because hypothyroidism can cause fertility problems, women who have trouble getting pregnant often get tested for thyroid problems.
Your doctor may use several blood tests to confirm a diagnosis of hyperthyroidism and find its cause. Imaging tests, such as a thyroid scan, can also help diagnose and find the cause of hyperthyroidism.
It can also cause a wide variety of signs and symptoms:
- 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.
- Sudden weight loss, even when your appetite and the amount and type of food you eat remain the same or even increase
- Rapid heartbeat (tachycardia) — commonly more than 100 beats a minute — irregular heartbeat (arrhythmia) or pounding of your heart (palpitations)
- Increased appetite
- Nervousness, anxiety and irritability
- Tremor — usually a fine trembling in your hands and fingers
- Changes in menstrual patterns
- Increased sensitivity to heat
- Changes in bowel patterns, especially more frequent bowel movements
- An enlarged thyroid gland (goiter), which may appear as a swelling at the base of your neck
- Fatigue, muscle weakness
- Difficulty sleeping
- Skin thinning
- Fine, brittle hair
- Graves’ ophthalmopathy=An autoimmune disease that is frequently associated with hyperthyroidism.
- Sometimes an uncommon problem called Graves’ ophthalmopathy may affect your eyes, especially if you smoke. In this disorder, your eyeballs protrude beyond their normal protective orbits when the tissues and muscles behind your eyes swell. This pushes the eyeballs forward so far that they actually bulge out of their orbits. This can cause the front surface of your eyeballs to become very dry. Eye problems often improve without treatment.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.
- Protruding eyeballs
- Red or swollen eyes
- Excessive tearing or discomfort in one or both eyes
- Light sensitivity, blurry or double vision, inflammation, or reduced eye movementIf you experience unexplained weight loss, a rapid heartbeat, unusual sweating, swelling at the base of your neck or other symptoms associated with hyperthyroidism, see your doctor. It’s important to completely describe the changes you’ve observed, because many signs and symptoms of hyperthyroidism may be associated with a number of other conditions.Causes: A number of conditions, including Graves’ disease, toxic adenoma, Plummer’s disease (toxic multi-nodular goiter) and thyroiditis, can cause hyperthyroidism.What other health problems could I have because of hyperthyroidism?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-related problems
- an eye disease called Graves’ ophthalmopathy that can cause double vision, light sensitivity, and eye pain, and rarely can lead to vision loss
- thinning bones and osteoporosis
When to go to the Doctor:
Any of these signs or symptoms listed above you have that where never checked out by the doctor or if the new symptom (s) just recently started and where never diagnosed by the MD. 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. Also, if you are at a age that makes you in a age group that is more common to have this disease than have your MD check you out to see if you have the disease.
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 with what you need to do.
Several treatment options are available if you have hyperthyroidism:
Several treatments for hyperthyroidism exist. The best approach for you depends on your age, physical condition, the underlying cause of the hyperthyroidism, personal preference and the severity of your disorder:
- Radioactive iodine. Taken by mouth, radioactive iodine is absorbed by your thyroid gland, where it causes the gland to shrink and symptoms to subside, usually within three to six months. Because this treatment causes thyroid activity to slow considerably, causing the thyroid gland to be underactive (hypothyroidism), you may eventually need to take medication every day to replace thyroxine. Used for more than 60 years to treat hyperthyroidism, radioactive iodine has been shown to be generally safe.
- Anti-thyroid medications. These medications gradually reduce symptoms of hyperthyroidism by preventing your thyroid gland from producing excess amounts of hormones. They include propylthiouracil and methimazole (Tapazole). Symptoms usually begin to improve in six to 12 weeks, but treatment with anti-thyroid medications typically continues at least a year and often longer. For some people, this clears up the problem permanently, but other people may experience a relapse. Both drugs can cause serious liver damage, sometimes leading to death. Because propylthiouracil has caused far more cases of liver damage, it generally should be used only when you can’t tolerate methimazole. A small number of people who are allergic to these drugs may develop skin rashes, hives, fever or joint pain. They also can make you more susceptible to infection.
- Beta blockers. These drugs are commonly used to treat high blood pressure. They won’t reduce your thyroid levels, but they can reduce a rapid heart rate and help prevent palpitations. For that reason, your doctor may prescribe them to help you feel better until your thyroid levels are closer to normal. Side effects may include fatigue, headache, upset stomach, constipation, diarrhea or dizziness.
- Surgery (thyroidectomy). If you’re pregnant or otherwise can’t tolerate anti-thyroid drugs and don’t want to or can’t have radioactive iodine therapy, you may be a candidate for thyroid surgery, although this is an option in only a few cases.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.
If Graves’ disease affects your eyes (Graves’ ophthalmopathy), you can manage mild signs and symptoms by avoiding wind and bright lights and using artificial tears and lubricating gels. If your symptoms are more severe, your doctor may recommend treatment with corticosteroids, such as prednisone, to reduce swelling behind your eyeballs. In some cases, a surgical procedure may be an option:
- Orbital decompression surgery. In this surgery, your doctor removes the bone between your eye socket and your sinuses — the air spaces next to the eye socket. When the procedure is successful, it improves vision and provides room for your eyes to return to their normal position. But there is a risk of complications, including double vision that persists or appears after surgery.
- Eye muscle surgery. Sometimes scar tissue from Graves’ ophthalmopathy can cause one or more eye muscles to be too short. This pulls your eyes out of alignment, leading to double vision. Eye muscle surgery may help correct double vision by cutting the affected muscle from the eyeball and reattaching it farther back. The goal is to achieve single vision when you read and look straight ahead. In some cases, you may need more than one operation to attain these results.
Although hyperthyroidism can be serious don’t 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.