- Arrhythmias, autoimmune, benign, biopsy, bradycardia, cancerous, cretinism, De Quervain's thyroiditis, diabetes mellitus, exophthalmia, exophthalmos, FANA, fluorescent antinuclear antibody test, goiter, Graves' disease, Graves' ophthalmopathy, hyperparathyroidism, hyperthyroid, hyperthyroidism, hypocalcemia, hypoparathyroidism, hypothyroidism, IGT, impaired glucose tolerance, intrinsic factor, iodine, malignant, myxedema, non-cancerous, nuclear scan, osteoporosis, parathyroid, parathyroid hormone, pernicious anemia, PTH, subclinical hyperthyroidism, subclinical hypothyroidism, tachycardia, tetany, thyroid storm, thyroidectomy, thyroiditis, thyrotoxicosis, ultrasound, vitamin B12, vitiligo.
- Hormonal disorders or endocrine disorders, including thyroid disorders, are illnesses that occur when the body releases too many or too few hormones. Hormones are chemicals messengers that are released into the bloodstream. Hormones send messages to cells throughout the body in order to regulate bodily functions, such as growth, metabolism, and sexual development. As a result, individuals with hormonal disorders experience a disruption in such bodily functions.
- Thyroid disorders are among the most common medical conditions but, because their symptoms often appear gradually over time, they are commonly misdiagnosed. There are four main types of thyroid disease: hyperthyroidism or too much thyroid hormone; hypothyroidism or too little thyroid hormone; benign (non-cancerous) thyroid disease; and thyroid cancer.
- The thyroid gland is a small, butterfly-shaped gland located in the base of the neck on both sides of the lower part of the voice box (larynx) and upper part of the wind pipe (trachea). The thyroid produces hormones, called thyroxine (T4) and triiodothyronine (T3), which affect the body's metabolism and energy level. Thyroid hormone is also produced in response to thyroid stimulating hormone (TSH, also known as thyrotropin) secreted by the pituitary gland.
- Release of thyroid hormones is controlled by the hypothalamus and pituitary gland, both found deep inside the brain. One of the most important features of the endocrine system is its regulation (control) by negative feedback. This means that the glands that stimulate the release of a hormone (for example, the pituitary) from another gland (for example, the thyroid) are eventually shut off, in a sense, so that too much hormone is not produced.
- Thyroid disorders affect some 4.5 million Americans. At least 600,000 of them have yet to be diagnosed.
- General: Once individuals are diagnosed with hypothyroidism (underactive thyroid) or Hashimoto's thyroiditis, they receive man-made hormones to make up for the decreased hormone levels. Treatment is life-long. Some individuals may need to have their thyroid gland surgically removed. These people will need to take hormones for the rest of their lives, but they are able to live normal, healthy lives.
- Individuals should tell their healthcare providers if they are taking any other drugs (prescription or over-the-counter), herbs, or supplements because they may interact with treatment. For instance, a cholesterol lowering medication called cholestyramine (Questran®), an ingredient in some antacids called aluminum hydroxide, sodium polystyrene sulfonate (Kayexalate®), an anti-ulcer drug called sucralfate (Carafate®), iron supplements, calcium supplements, and soy may interact with treatment.
- Thyroid hormone replacement therapy: Individuals usually receive thyroid hormone replacement therapy with levothyroxine (Levothroid®, Levoxyl®, Synthroid®, or Unithroid®). This man-made hormone is identical to the natural thyroid hormone called thyroxine. The medication is taken by mouth every day for life to help the body return to normal functioning. Levothyroxine is the most commonly prescribed thyroid hormone replacement drug. A synthetic form of thyroid hormone, liothyronine (Cytomel®), may also be prescribed. Thyrolar® (Liotrix) is another synthetic thyroid drug that contains both L-triiodothyronine (T3) and levothyroxine sodium (T4).
- Natural thyroid hormone replacement drugs are made from the desiccated (dried and powdered) thyroid glands of pigs and are available by prescription. Dessicated thyroid drugs have been available since the late 1800s, however since the early 1960s have been largely replaced with use of synthetic levothyroxine. All commercially available brands of desiccated thyroid contain a mixture of thyroid hormones, T4 (thyroxine) and T3 (triiodothyronine). Among the most well known brands of desiccated thyroid in the United States is Armour® Thyroid. Natural thyroid hormone agents are also sometimes called natural thyroid, natural thyroid hormones, pork thyroid, thyroid USP, thyroid extract, or thyroid BP.
- Individuals should visit their healthcare providers every six to 12 months to monitor their hormone levels. Over time, the dosage may be changed. If the dose is too high, individuals may develop a condition called osteoporosis, which causes the bones to become hollow and brittle. Also, excessive doses may lead to irregular heartbeats (arrhythmias). In order to prevent complications of overdose, individuals with a history of heart disease, osteoporosis, or severe hypothyroidism may receive smaller doses that are gradually increased over time.
- Surgery: If an individual patient develops a goiter that does not respond to hormone therapy, the thyroid may need to be surgically removed (called thyroidectomy). Although goiters generally do not cause pain, a large goiter can interfere with swallowing or breathing and it may affect the individual's appearance and self-esteem. Individuals can live long, healthy lives without the thyroid gland. However, they must take hormone pills called levothyroxine (Levothroid®, Levoxyl®, Synthroid® or Unithroid®) for the rest of their lives.
- Several treatments for hyperthyroidism exist. The best approach depends on age, physical health, and the severity of the condition.
- Radioactive iodine: Taken by mouth, radioactive iodine is absorbed by the 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 and for the thyroid gland to shrink in size, individuals may eventually need to take a medication every day to achieve adequate thyroid hormone levels.
- Anti-thyroid medications: Anti-thyroid medications gradually reduce symptoms of hyperthyroidism by preventing the thyroid gland from producing excess amounts of hormones. They include propylthiouracil (PTU) 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 individuals, symptoms of hyperthyroidism disappear completely, but others may experience a relapse.
- Beta blockers: Beta blockers are commonly used to treat hypertension (high blood pressure). They will not reduce thyroid levels, but they can reduce a rapid heart rate and help prevent palpitations. Individuals with hyperthyroidism may be prescribed beta blockers until the thyroid levels are closer to normal and heart symptoms disappear.
- Surgery: Thyroidectomy is used when the individual cannot tolerate anti-thyroid drugs and does not want to have radioactive iodine therapy, although this is an option in only a few cases. These individuals may be at an increased risk for complications when using drugs or radioactive therapy.
- In a thyroidectomy, a doctor removes most of the thyroid gland. Risks of this surgery include damage to the vocal cords and parathyroid glands. Parathyroid glands are four tiny glands located on the back of the thyroid gland that help control the level of calcium in the blood. Individuals undergoing a thyroidectomy will need lifelong treatment with levothyroxine (Synthroid®) to supply the body with normal amounts of thyroid hormone. If the parathyroid glands also are removed, individuals will need medication to keep the blood-calcium levels normal.
- This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
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Types of thyroid disorders
- Hyperthyroidism: Hyperthyroidism occurs when the thyroid gland produces too much thyroxine. As a result, the individual's metabolism increases dramatically, leading to weight loss and irregular heartbeat.
- Most individuals fully recover from hyperthyroidism with treatment. However, if left untreated, the condition may be life threatening. Complications may include heart problems, brittle bones, and thyrotoxic crisis (sudden release of thyroid hormone). Thyrotoxic crisis occurs when symptoms suddenly become extreme, causing fever, increased heartbeat, and sometimes delirium.
- The most common cause of hyperthyroidism is Grave's disease. In Graves' disease, a malfunction in the body's immune system releases abnormal antibodies that mimic thyroid stimulating hormone (TSH). Spurred by these false signals to produce, the thyroid's hormone factories work overtime and produce an excess of thyroid hormone.
- Exophthalmia, also known as exophthalmos, is bulging of the eyes. Exophthalmia is a characteristic of individuals with Grave's disease. Exophthalmia occurs in about 40-60% of individuals who suffer from Grave's disease.
- Non-cancerous tumors (abnormal growths) on the thyroid gland may also lead to hyperthyroidism. Some tumors may cause the thyroid to produce excess thyroid hormone. This causes the thyroid to become enlarged.
- Hyperthyroidism may also occur if the thyroid gland becomes inflamed, called thyroiditis. When the gland is swollen, stored thyroid hormone may leak into the bloodstream.
- Hypothyroidism: Hypothyroidism occurs when the thyroid gland does not produce enough thyroid hormone.
- A condition called Hashimoto's thyroiditis is the most common cause of hypothyroidism in the United States. Thyroiditis is an inflammation of the thyroid gland not due to infection. Several types of thyroiditis exist and the treatment is different for each. Hashimoto's thyroiditis occurs when the individual's immune system attacks the thyroid gland, causing low levels of thyroid hormone. Researchers have not discovered why the immune system mistakes the thyroid for a harmful invader, such as a virus. It has been suggested that many factors lead to the disorder, including age, heredity, and gender. This is because the condition is most common among middle-aged women. It also common among biological family members.
- Other less common types of hypothyroidism include De Quervain's thyroiditis and silent thyroiditis. In De Quervain's thyroiditis, the thyroid gland generally swells rapidly and is very painful and tender. In silent thyroiditis, there is no pain or needle biopsy (removal of tissue for examination).
- Hypothyroidism may also occur if individuals do not consume enough iodine in the diet. This is most common in poor countries where malnutrition is common. Iodine is an essential element that helps the thyroid gland produce hormones.
- A goiter is an enlargement of the thyroid gland. Although generally not uncomfortable, goiter can interfere with swallowing or breathing. Goiters are more common in women and older adults. The most common cause of goiter is a shortage of iodine in the diet in areas where the soil is deficient in iodine. Although goiters generally do not cause pain, a large goiter may interfere with swallowing or breathing and it may affect the individual's appearance and self-esteem. In many cases, goiters will be cured once hormone replacement therapy is started. However, some individuals may need to have their goiter surgically removed. Goiters are typical of hypothyroidism.
- Individuals should visit their healthcare providers every six to 12 months to monitor their hormone levels. Over time, the dosage of thyroid medication may need to be changed. If the dose is too high, individuals may develop a condition called osteoporosis, which causes the bones to become hollow and brittle. Also, excessive doses may lead to irregular heartbeats (arrhythmias). In order to prevent complications of overdose, individuals with a history of heart disease, osteoporosis, or severe hypothyroidism may receive smaller doses that are gradually increased over time.
- Thyroid nodules: Thyroid nodules are lumps that commonly arise within an otherwise normal thyroid gland. Often these abnormal growths of thyroid tissue are located at the edge of the thyroid gland so they can be felt as a lump in the throat. When they are large or when they occur in very thin individuals, they can even sometimes be seen as a lump in the front of the neck. One in 12-15 young women has a thyroid nodule, and one in 40 young men has a thyroid nodule. More than 95% of all thyroid nodules are benign (non-cancerous growths). Some nodules are actually cysts that are filled with fluid rather than thyroid tissue. Most individuals will develop a thyroid nodule by the time they are 50 years old. The incidence of thyroid nodules increases with age; 50% of 50 year olds will have at least one thyroid nodule, 60% of 60 year olds will have at least one thyroid nodule, and 70% of 70 year olds will have at least one thyroid nodule. Individuals do not have to have hypo- and hyperthyroidism to have nodules of the thyroid gland.
- Thyroid cancer: Many types of tumors can develop in the thyroid gland. Most of these tumors are benign (non-cancerous). Others are malignant (cancerous), which means they can spread into nearby tissues and to other parts of the body. Anyone can get cancer of the thyroid gland, but certain factors may increase the risk. Risk factors include: being between ages 25-65; being a woman; being Asian; having a family member who has had thyroid disease; or having radiation treatments to the head or neck.
- Hyperparathyroidism: The parathyroid glands regulate serum calcium and phosphorus levels through the secretion of parathyroid hormone (PTH), which raises serum calcium levels while lowering the serum phosphorus concentration. The regulation of PTH secretion occurs through a negative feedback loop in which calcium-sensing receptors on the membranes of parathyroid cells trigger decreased PTH production as serum calcium concentrations rise. Primary hyperparathyroidism, which accounts for most presentations of hyperparathyroidism, results from excessive release of PTH and manifests as hypercalcemia. In 80% of patients with hyperparathyroidism, the symptoms of hypercalcemia (high blood levels of calcium) are mild or not notable.
- Hypoparathyroidism: Hypoparathyroidism is secretion of too little parathyroid hormone. The symptoms of hypoparathyroidism are the same as hypocalcemia (low blood calcium levels). Symptoms can range from quite mild (tingling in the hands, fingers, and around the mouth) to more severe forms of muscle cramps leading all the way to tetany (severe muscle cramping of the entire body), and rarely convulsions.
Copyright © 2011 Natural Standard (www.naturalstandard.com)
The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.