Hypothyroidism Definition: Hypothyroidism, also known as underactive thyroid disease, is a disorder wherein the thyroid gland does not produce enough thyroid hormones. Secondary causes: This refers to the conditions that cause the pituitary gland to fail. At first, you may barely notice the symptoms of hypothyroidism, such as fatigue and weight gain. The causes of hypothyroidism in women and men are similar. Both iodine deficiency and excess can cause hypothyroidism. In this condition, your immune system makes cells that attack your thyroid gland, which keeps it from working properly. It's also common in people with another immune system disorder, such as type 1 diabetes and vitiligo. 5 Surprising Environmental Causes of Hypothyroidism. This content does not have an Arabic version. © 1998-2021 Mayo Foundation for Medical Education and Research (MFMER). The most common cause of hypothyroidism is Hashimoto's thyroiditis (or autoimmune hypothyroidism), a form of thyroid inflammation caused by your own immune system. Goodbye fatigue! "Mayo," "Mayo Clinic," "MayoClinic.org," "Mayo Clinic Healthy Living," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research. 1. In: Ferri's Clinical Advisor 2019. Primary causes of hypothyroidism are much more common. Most cases of an underactive thyroid are caused by the immune system attacking the thyroid gland and damaging it, or by damage that occurs as a result of treatments for thyroid cancer or an overactive thyroid. Have an autoimmune disease, such as type 1 diabetes or celiac disease, Have been treated with radioactive iodine or anti-thyroid medications, Received radiation to your neck or upper chest, Have had thyroid surgery (partial thyroidectomy), Have been pregnant or delivered a baby within the past six months. When your thyroid doesn't produce enough hormones, the balance of chemical reactions in your body can be upset. The most common cause of hypothyroidism is an autoimmune disorder known as Hashimoto's thyroiditis. Causes of Hypothyroidism. Next review due: 27 April 2021, Great Ormond Street Hospital for Children, congenital hypothyroidism and how it's treated. The definition of hypothyroidism is based on statistical reference ranges of the relevant biochemical parameters and is increasingly a matter of debate. An underactive thyroid (hypothyroidism) is when your thyroid gland does not produce enough of the hormone thyroxine (also called T4). Its signs and symptoms include intense cold intolerance and drowsiness followed by profound lethargy and unconsciousness. It's usually picked up during routine screening soon after birth. Causes There are many causes of hypothyroidism, such as: Hashimoto’s disease Hashimoto’s disease is the most common cause of hypothyroidism. Mayo Clinic does not endorse companies or products. 1 Lymphocytic thyroiditis, the most common cause of hypothyroidism, is a hereditary disease that causes the immune system to attack the thyroid as if it doesn’t belong. Menu https://www.merckmanuals.com/professional/pediatrics/endocrine-disorders-in-children/hypothyroidism-in-infants-and-children. Let’s explore seven of the most common reasons that hypothyroidism develops. If you have signs or symptoms of myxedema, you need immediate emergency medical treatment. In today's video we cover the causes of hypothyroidism, also known as ROOT CAUSES. And over time, the dose you need may change. It … Hypothyroidism (underactive thyroid) is a condition in which your thyroid gland doesn't produce enough of certain crucial hormones. The most common of these primary causes is an autoimmune condition called Hashimoto’s disease. Other causes of hypothyroidism include: Surgery . Hypothyroidism: Should I take iodine supplements? Less often, hypothyroidism may result from one of the following: Although anyone can develop hypothyroidism, you're at an increased risk if you: Untreated hypothyroidism can lead to a number of health problems: Myxedema. Here is a rundown of the most common causes of hypothyroidism in the U.S. AUTOIMMUNE THYROIDITIS (HASHIMOTO’S DISEASE) “Thyroiditis” means inflammation of the thyroid. Available to diagnose hypothyroidism disorders occur when your thyroid issues, causes of hypothyroidism need emergency. That hypothyroidism develops hormone is usually simple, safe and effective once you and your...., and external radiation therapy are other frequent causes of hypothyroidism is based on statistical reference ranges the! Joint pain, stiffness or swelling in your joints, Heavier than normal or irregular menstrual periods of! Affect the thyroid much or too little iodine in the United States, where iodine is a condition called ’... 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