Learn About Hypothyroidism

What is the definition of Hypothyroidism?

Hypothyroidism is a condition in which the thyroid gland does not make enough thyroid hormone. This condition is often called underactive thyroid.

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What are the alternative names for Hypothyroidism?

Myxedema; Adult hypothyroidism; Underactive thyroid; Goiter - hypothyroidism; Thyroiditis - hypothyroidism; Thyroid hormone - hypothyroidism

What are the causes of Hypothyroidism?

The thyroid gland is an important organ of the endocrine system. It is located at the front of the neck, just above where your collarbones meet. The thyroid makes hormones that control the way every cell in the body uses energy. This process is called metabolism.

Brain-thyroid link

Hypothyroidism is more common in women and people over age 50.

The most common cause of hypothyroidism is thyroiditis. Swelling and inflammation damage the thyroid gland's cells.

Causes of this problem include:

  • The immune system attacking the thyroid gland
  • Viral infections (common cold) or other respiratory infections
  • Pregnancy (often called postpartum thyroiditis)

Other causes of hypothyroidism include:

  • Certain medicines, such as lithium and amiodarone, and some types of chemotherapy
  • Congenital (birth) defects
  • Radiation treatments to the neck or brain to treat different cancers
  • Radioactive iodine used to treat an overactive thyroid gland
  • Surgical removal of part or all of the thyroid gland
  • Sheehan syndrome, a condition that may occur in a woman who bleeds severely during pregnancy or childbirth and causes the destruction of the pituitary gland
  • Pituitary tumor or pituitary surgery
What are the symptoms of Hypothyroidism?

Early symptoms:

  • Hard stools or constipation
  • Feeling cold (wearing a sweater when others are wearing a t-shirt)
  • Fatigue or feeling slowed down
  • Heavier and irregular menstrual periods
  • Joint or muscle pain
  • Paleness or dry skin
  • Sadness or depression
  • Thin, brittle hair or fingernails
  • Weakness
  • Weight gain

Late symptoms, if untreated:

  • Decreased taste and smell
  • Hoarseness
  • Puffy face, hands, and feet
  • Slow speech
  • Thickening of the skin
  • Thinning of eyebrows
  • Low body temperature
  • Slow heart rate
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What are the current treatments for Hypothyroidism?

Treatment is aimed at replacing the thyroid hormone you are lacking.

Levothyroxine is the most commonly used medicine:

  • You will be prescribed the lowest dose possible that relieves your symptoms and brings your blood hormone levels back to normal.
  • If you have heart disease or you are older, your provider may start you on a very small dose.
  • Most people with an underactive thyroid will need to take this medicine for life.
  • Levothyroxine is usually a pill, but some people with very severe hypothyroidism first need to be treated in the hospital with intravenous levothyroxine (given through a vein).

When starting you on your medicine, your provider may check your hormone levels every 2 to 3 months. After that, your thyroid hormone levels should be monitored at least once every year.

When you are taking thyroid medicine, be aware of the following:

  • Do not stop taking the medicine, even when you feel better. Continue taking it exactly as your provider prescribed.
  • If you change brands of thyroid medicine, let your provider know. Your levels may need to be checked.
  • What you eat can change the way your body absorbs thyroid medicine. Talk with your provider if you are eating a lot of soy products or are on a high-fiber diet.
  • Thyroid medicine works best on an empty stomach and when taken 1 hour before any other medicines. Ask your provider if you should take your medicine at bedtime. Taking it at bedtime may allow your body to absorb the medicine better than taking it in the daytime.
  • Wait at least 4 hours after taking thyroid hormone before you take fiber supplements, calcium, iron, multivitamins, aluminum hydroxide antacids, colestipol, or medicines that bind bile acids.

While you are taking thyroid replacement therapy, tell your provider if you have any symptoms that suggest your dose is too high, such as:

  • Anxiety
  • Palpitations
  • Rapid weight loss
  • Restlessness or shakiness (tremors)
  • Sweating
Who are the top Hypothyroidism Local Doctors?
Highly rated in

University Of Naples Federico II

Pediatric Endocrine Unit, Department Of Translational Medical Sciences 
Naples, IT 80131

Mariacarolina Salerno is in Naples, Italy. Salerno is rated as an Elite expert by MediFind in the treatment of Hypothyroidism. They are also highly rated in 26 other conditions, according to our data. Their top areas of expertise are Hypothyroidism, Pituitary Dwarfism, Hashimoto Thyroiditis, and Isolated Growth Hormone Deficiency.

Highly rated in

University Of Bern

Bern, BE, CH 3010

Nicolas Rodondi is in Bern, Switzerland. Rodondi is rated as an Elite expert by MediFind in the treatment of Hypothyroidism. He is also highly rated in 20 other conditions, according to our data. His top areas of expertise are Hypothyroidism, Acute Coronary Syndrome, Atrial Fibrillation, and Hyperthyroidism.

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Highly rated in

University Vita Salute San Raffaele

Department Of Pediatrics, Endocrine Unit, Vita Salute San Raffaele University 
Milan, IT 

Maria Vigone is in Milan, Italy. Vigone is rated as an Elite expert by MediFind in the treatment of Hypothyroidism. She is also highly rated in 5 other conditions, according to our data. Her top areas of expertise are Congenital Hypothyroidism, Isolated Growth Hormone Deficiency, Neonatal Hypothyroidism, and Hypothyroidism.

What is the outlook (prognosis) for Hypothyroidism?

In most cases, thyroid hormone level becomes normal with proper treatment. You will likely take a thyroid hormone medicine for the rest of your life.

What are the possible complications of Hypothyroidism?

Myxedema crisis (also called myxedema coma), the most severe form of hypothyroidism, is rare. It occurs when thyroid hormone levels get very, very low. The severe hypothyroid crisis is then caused by an infection, illness, exposure to cold, or certain medicines (opiates are a common cause) in people with severe hypothyroidism.

Myxedema crisis is a medical emergency that must be treated in the hospital. Some people may need oxygen, breathing assistance (ventilator), fluid replacement, and intensive-care nursing.

Symptoms and signs of myxedema coma include:

  • Below normal body temperature
  • Decreased breathing
  • Low systolic blood pressure
  • Low blood sugar
  • Unresponsiveness
  • Inappropriate or uncharacteristic moods

People with untreated hypothyroidism are at increased risk of:

  • Infection
  • Infertility, miscarriage, giving birth to a baby with birth defects
  • Heart disease because of higher levels of LDL (bad) cholesterol
  • Heart failure
When should I contact a medical professional for Hypothyroidism?

Call your provider if you have symptoms of hypothyroidism.

If you are being treated for hypothyroidism, call your provider if:

  • You develop chest pain or rapid heartbeat
  • You have an infection
  • Your symptoms get worse or do not improve with treatment
  • You develop new symptoms
Endocrine glands
Primary and secondary hypothyroidism
What are the latest Hypothyroidism Clinical Trials?
Clinical and Basic Investigations Into Known and Suspected Congenital Disorders of Glycosylation
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Effect of Thyroid Replacement Therapy on Thyroid Structure in Patients With Subclinical Hypothyroidism
What are the Latest Advances for Hypothyroidism?
Systematic review and meta-analysis of the efficacy and pregnancy outcomes of levothyroxine sodium tablet administration in pregnant women complicated with hypothyroidism.
Effect of Levothyroxine on Pregnancy Outcomes in Pregnant Women With Hypothyroxinemia: An Interventional Study.
Tired of the same old research?
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Comparison Among Two Liquid Formulations of L-thyroxine in the Treatment of Congenital Hypothyroidism in the First Month of Life: A Pilot Study.
Who are the sources who wrote this article ?

Published Date : August 29, 2020
Published By : Brent Wisse, MD, board certified in Metabolism/Endocrinology, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

What are the references for this article ?

Brent GA, Weetman AP. Hypothyroidism and thyroiditis. In: Melmed S, Auchus RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 13.

Garber JR, Cobin RH, Gharib H, et al. Clinical practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association. Endocr Pract. 2012;18(6):988-1028. PMID: 23246686 pubmed.ncbi.nlm.nih.gov/23246686/.

Jonklaas J, Bianco AC, Bauer AJ, et al; American Thyroid Association Task Force on Thyroid Hormone Replacement. Guidelines for the treatment of hypothyroidism: prepared by the American Thyroid Association task force on thyroid hormone replacement. Thyroid. 2014;24(12):1670-1751. PMID: 25266247 pubmed.ncbi.nlm.nih.gov/25266247/.