Low thyroid function, hypothyroidism, occurs when the body does not produce enough thyroid hormone. The thyroid, located at the front of the neck, plays a key role in the regulation of metabolism. Every cell in the body depends on thyroid hormones to function properly. Low thyroid function can affect everything from emotional stability to weight. Approximately 10 million Americans have been diagnosed with hypothyroidism. Speak with a family physician or endocrinologist if you think you may be hypothyroid.
Symptoms
Lacking in thyroid hormone causes the functions of the body to slow down, which results in physical and emotional sluggishness. Symptoms can include constipation, fatigue, joint pain, muscle weakness, irritability, inability to focus and concentrate, memory loss, hair loss and weight gain. Low thyroid function can also cause menstrual disorders in women, may cause depression and a change in hair, skin and nails. According to Endocrineweb.com, symptoms can vary in severity and can be different from person to person.
Causes
A common cause for low thyroid function is inflammation of the thyroid gland. Autoimmune thyroiditis, or Hashimoto's, results when the body's immune system mistakenly attacks the thyroid gland, causing inflammation that destroys part of the thyroid. Additionally, medical treatments, including partial or complete removal of the thyroid gland due to goiter, cancer or nodules, can result in low thyroid function, Endocrineweb.com notes. Sometimes, improper function of the pituitary gland can affect the production of thyroid hormones and result in low thyroid function.
Blood Tests
The pituitary gland produces TSH, thyroid stimulating hormone. TSH is needed to tell the thyroid gland to produce the additional thyroid hormones T4 and T3. Insufficient TSH can indicate hypothyroidism. The National Institutes of Health's Medline Plus lists normal ranges for TSH to be between 0.4 and 4.0. Anything above a 2.0 or 3.0 warrants additional blood work. The amount of triiodothyronine, T3, and thyroxine, T4, are also tested to determine thyroid function. Low levels of T3 and T4, combined with high levels of TSH are considered to be low thyroid function or hypothyroidism. Additional blood work and testing may be necessary and lab ranges can vary.
Warning
Left untreated, hypothyroidism can progress, causing symptoms to intensify. The excess TSH can cause a goiter, or a swelling of the thyroid gland. Rarely, complications such as coma, heart failure or severe depression can occur.
Treatment
Thyroid hormone replacement is prescribed to bring the thyroid hormone levels into the normal range. Hypothyroidism is a treatable disease. However, finding the right dose can be a long and difficult process for some, Endocrineweb.com notes. The most commonly prescribed medication is T4. Sometimes, a combination of T4 and T3 is needed and brings a patient the most relief. It can take one to three weeks before a patient may notice a change in symptoms. A doctor should consider the lab results of a patient as well as their symptoms to determine the correct dose and type of medication.
