The thyroid gland is situated at the front of the neck. It produces thyroid hormone, which acts at every cell in the body, largely to control its rate of metabolism. Low thyroid hormone decreases the metabolism and causes hypothyroidism. This disease causes symptoms such as fatigue, weakness, weight gain, depression, skin and hair problems, cold intolerance and muscle cramps. There are three types of hypothyroidism, and treatment is generally the same for all. Consult a physician for the diagnosis and management of hypothyroidism and other diseases.
Primary Hypothyroidism
Primary hypothyroidism is caused by dysfunction of the thyroid to the point that it doesn't produce or release adequate levels of thyroid hormone. It can be caused by an immune system reaction against the thyroid. Also, iodine is required to make thyroid hormone, so iodine deficiency can lead to primary hypothyroidism. Occasionally, inherited diseases or developmental problems can cause primary hypothyroidism. It can also be caused by some medications, such as lithium, used to treat hypothyroidism.
Secondary Hypothyroidism
Secondary hypothyroidism is caused by a deficiency of thyroid stimulating hormone, or TSH. This hormone is produced by the pituitary. It's released into the bloodstream, where it travels to the thyroid gland to signal it to make and release thyroid hormone. Damage to the pituitary, such as by a tumor, surgery or radiation, can cause secondary hypothyroidism, according to "Current Medical Diagnosis and Treatment 2011."
Tertiary Hypothyroidism
A part of the brain called the hypothalamus secretes thyrotropin-releasing hormone -- TRH, which stimulates the pituitary to release the TSH that acts on the thyroid gland. Tertiary hypothyroidism is caused by problems in the hypothalamus that prevent it from producing TRH. Strokes and benign and cancerous tumors are examples of problems that can affect TRH secretion, says the textbook "Harrison's Principles of Internal Medicine."
Treatments and Supplements for Hypothyroidism
Hypothyroidism requires replacement with thyroid hormone. A physician can provide a prescription for an appropriate dose of thyroid hormone. According to the Mayo Clinic, most physicians recommend synthetic thyroid hormone. However, natural extracts of thyroid hormone from the thyroid glands of pigs are available as well, also by prescription. The Food and Drug Administration doesn't regulate the glandular concentrates sold in natural foods stores, so their purity and strength are not guaranteed.
References
- "Harrison's Principles of Internal Medicine"; Anthony S Fauci, et al.; 17th Ed 2008
- "Robbins and Cotran Pathologic Basis of Disease"; Vinay Kumar, et al.; 8th Ed 2009
- "Current Medical Diagnosis and Treatment 2011"; Stephen McPhee, et al.; 50th Ed 2010
- Mayo Clinic: Hypothyroidism: Alternative Medicine
