The endocrine system is made up of glands that are located in the brain and throughout the body. Glands produce hormones, which are chemical messengers that regulate the function of various organ systems. One of these glands, the thyroid, is located at the front of the throat. The thyroid gland is small and shaped like a butterfly. It produces three hormones: thyroxine, triiodothyronine, and calcitonin.
Causes
Hypothyroidism, or decreased thyroid hormone levels, can be caused by autoimmune disorders. Hashimoto’s disease, an autoimmune disorder, is the most common cause of hypothyroidism, according to the Merck Manuals Online Medical Library.
Treatment for another thyroid condition, hyperthyroidism, can also result in hypothyroidism. Hyperthyroidism is a condition wherein the thyroid produces too much hormone. Treatment involves reducing thyroid hormone production via the use of radioactive iodine, antithyroid drugs or surgery. This can lead to an underproduction of thyroid hormone, and thus hypothyroidism.
Diseases of other glands that influence the thyroid, such as the pituitary gland, can also lead to hypothyroidism. Iodine deficiency and thyroid inflammation are other causes of hypothyroidism.
Effects
The University of Maryland Medical Center (UMMC) explains that those who suffer from hypothyroidism commonly experience weight gain, fatigue, excessive menstrual flow, constipation and a host of other symptoms related to the slowing down of the metabolism. These symptoms can be subtle, with a gradual onset. The American Thyroid Association advises that symptoms vary from person to person and can be confused with the symptoms of other disorders.
Diagnosis
Doctors who suspect hypothyroidism will examine the medical and family history of the patient, inquiring about past incidence of thyroid conditions. A physical exam can identify characteristic symptoms such as slowed reflexes and heart rate. UMMC says blood tests that measure the levels of thyroid-stimulating hormone and thyroxine in the blood are also useful in diagnosing hypothyroidism.
Treatment
Hypothyroidism is treated through thyroid hormone replacement medication that boosts thyroxine hormone to normal levels in the body. Thyroxine pills are safe, with side effects only occurring when they are taken in inappropriate dosages. It can take a bit of experimentation to determine the precise level for each individual. Excessive doses of thyroxine can accelerate the heart rate and cause anxiety, heat intolerance and shortness of breath.
Prognosis
Hypothyroidism is incurable, according to the American Thyroid Association, but supplementing the body with synthetic thyroid hormone can provide complete relief from the disorder’s effects.
