Hypothyroidism is a condition in which the thyroid gland does not make enough thyroid hormone.
See also:
Myxedema; Adult hypothyroidism
Causes, incidence, and risk factorsThe thyroid gland is located in the front of the neck just below the voice box (larynx). It releases hormones that control metabolism.
The most common cause of hypothyroidism is inflammation of the thyroid gland, which damages the gland's cells. Autoimmune or Hashimoto's thyroiditis, in which the immune system attacks the thyroid gland, is the most common example of this. Some women develop hypothyroidism after pregancy (often referred to as "postpartum thyroiditis").
Other common causes of hypothyroidism include:
Certain drugs can cause hypothyroidism, including:
Risk factors include:
Early symptoms:
Late symptoms, if left untreated:
A physical examination may reveal a smaller than normal thyroid gland, although sometimes the gland is normal size or even enlarged (goiter). The examination may also reveal:
A chest x-raymay show an enlarged heart.
Laboratory tests to determine thyroid function include:
Lab tests may also reveal:
The purpose of treatment is to replace the thyroid hormone that is lacking. Levothyroxine is the most commonly used medication. Doctors will prescribe the lowest dose possible that effectively relieves symptoms and brings your TSH level to a normal range. If you have Heart disease or you are older, your doctor may start with a very small dose.
Lifelong therapy is required unless you have a condition called transient viral thyroiditis.
You must continue taking your medication even when your symptoms go away. When starting your medication, your doctor may check your hormone levels every 2 - 3 months. After that, your thyroid hormone levels should be monitored at least every year.
Important things to remember when you are taking thyroid hormone are:
After you start taking replacement therapy, tell your doctor if you have any symptoms of increased thyroid activity (hyperthyroidism) such as:
Myxedema coma is a medical emergency that occurs when the body's level of thyroid hormones becomes extremely low. It is treated with intravenous thyroid hormone replacement and steroid medications. Some patients may need supportive therapy (oxygen, breathing assistance, fluid replacement) and intensive-care nursing.
Expectations (prognosis)In most cases, thyroid levels return to normal with proper treatment. However, thyroid hormone replacement must be taken for the rest of your life.
Myxedema coma can result in death.
ComplicationsMyxedema coma, the most severe form of hypothyroidism, is rare. It may be caused by an infection, illness, exposure to cold, or certain medications in people with untreated hypothyroidism.
Symptoms and signs of myxedema coma include:
Other complications are:
People with untreated hypothyroidism are at increased risk for:
People treated with too much thyroid hormone are at risk for angina or heart attack, as well as osteoporosis (thinning of the bones).
Calling your health care providerCall your health care provider if you have symptoms of hypothyroidism (or myxedema).
If you are being treated for hypothyroidism, call your doctor if:
There is no prevention for hypothyroidism.
Screening tests in newborns can detect hypothyroidism that is present from birth (congenital hypothyroidism).
ReferencesFatourechi V. Subclinical hypothyroidism: an update for primary care physicians. Mayo Clin Proc. 2009;84(1):65-71.
Ladenson P, Kim M. Thyroid. In: Goldman L and Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders; 2007:chap 244.
Vaidya B, Pearce SH. Management of hypothyroidism in adults. BMJ. 2008;337.
Allahabadia A, Razvi S, Abraham P, Franklyn J. Diagnosis and treatment of primary hypothyroidism. BMJ. 2009 Mar 26;338.
Hypothyroidism is a condition in which the thyroid gland does not make enough thyroid hormone.
See also:
Myxedema; Adult hypothyroidism
Causes, incidence, and risk factorsThe thyroid gland is located in the front of the neck just below the voice box (larynx). It releases hormones that control metabolism.
The most common cause of hypothyroidism is inflammation of the thyroid gland, which damages the gland's cells. Autoimmune or Hashimoto's thyroiditis, in which the immune system attacks the thyroid gland, is the most common example of this. Some women develop hypothyroidism after pregnancy (often referred to as "postpartum thyroiditis").
Other common causes of hypothyroidism include:
Certain drugs can cause hypothyroidism, including:
Risk factors include:
Early symptoms:
Late symptoms, if left untreated:
A physical examination may reveal a smaller than normal thyroid gland, although sometimes the gland is normal size or even enlarged (goiter). The examination may also reveal:
A chest x-raymay show an enlarged heart.
Laboratory tests to determine thyroid function include:
Lab tests may also reveal:
The purpose of treatment is to replace the thyroid hormone that is lacking. Levothyroxine is the most commonly used medication. Doctors will prescribe the lowest dose possible that effectively relieves symptoms and brings your TSH level to a normal range. If you have heart disease or you are older, your doctor may start with a very small dose.
Lifelong therapy is required unless you have a condition called transient viral thyroiditis.
You must continue taking your medication even when your symptoms go away. When starting your medication, your doctor may check your hormone levels every 2 - 3 months. After that, your thyroid hormone levels should be monitored at least every year.
Important things to remember when you are taking thyroid hormone are:
After you start taking replacement therapy, tell your doctor if you have any symptoms of increased thyroid activity (hyperthyroidism) such as:
Myxedema coma is a medical emergency that occurs when the body's level of thyroid hormones becomes extremely low. It is treated with intravenous thyroid hormone replacement and steroid medications. Some patients may need supportive therapy (oxygen, breathing assistance, fluid replacement) and intensive-care nursing.
Expectations (prognosis)In most cases, thyroid levels return to normal with proper treatment. However, thyroid hormone replacement must be taken for the rest of your life.
Myxedema coma can result in death.
ComplicationsMyxedema coma, the most severe form of hypothyroidism, is rare. It may be caused by an infection, illness, exposure to cold, or certain medications in people with untreated hypothyroidism.
Symptoms and signs of myxedema coma include:
Other complications are:
People with untreated hypothyroidism are at increased risk for:
People treated with too much thyroid hormone are at risk for angina or heart attack, as well as osteoporosis (thinning of the bones).
Calling your health care providerCall your health care provider if you have symptoms of hypothyroidism (or myxedema).
If you are being treated for hypothyroidism, call your doctor if:
There is no prevention for hypothyroidism.
Screening tests in newborns can detect hypothyroidism that is present from birth (congenital hypothyroidism).
ReferencesFatourechi V. Subclinical hypothyroidism: an update for primary care physicians. Mayo Clin Proc. 2009;84(1):65-71.
Ladenson P, Kim M. Thyroid. In: Goldman L and Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders; 2007:chap 244.
Vaidya B, Pearce SH. Management of hypothyroidism in adults. BMJ. 2008;337.
Allahabadia A, Razvi S, Abraham P, Franklyn J. Diagnosis and treatment of primary hypothyroidism. BMJ. 2009 Mar 26;338.
Reviewed ByReview Date: 04/19/2010
Ari S. Eckman, MD, Division of Endocrinology and Metabolism, Johns Hopkins School of Medicine, Baltimore, MD. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
Do you feel tired and weak? Well, there could be many reasons for that, but a slow, underactive thyroid may be your problem. Let's talk about hypothyroidism - also known as Slow Thyroid.
Here's the thyroid. It's this butterfly shaped gland in your neck - just below the voice box.
The thyroid gland is known as the "master gland" of the body. It regulates our metabolism, so we don't act slow, like turtles, or fast, like jackrabbits.
This gland releases hormones that control many important things, like helping your heart pump blood, stimulating your brain and muscles, and helping you keep your body at a healthy temperature. When you have hypothyroidism, your thyroid gland does not make enough hormone, so you end up feeling a bit slow, and perhaps cold, like the turtle.
So, what causes a slow thyroid?
For at least 9 out of 10 folks, the cause is something called Hashimoto's thyroiditis... It's what we call an "autoimmune condition", where, for reasons that we don't quite understand, our own body attacks perfectly good thyroid tissue as though it were a foreign invader. This attack damages the thyroid gland, so much, that it can't put out enough hormone.
This attack happens much more often in women than in men, 10 and 20 times more often. Also, some women develop this condition soon after pregnancy, Why that happens? Nobody knows for sure!
So, how do you feel if you have a slow thyroid?
If it's just mildly slow, you might not feel anything at all, that's called subclinical hypothyroidism. On the other hand, you might be experiencing symptoms of a slow thyroid RIGHT NOW, but you just haven't connected the dots. You might have mild fatigue, memory or concentration problems. You may have a decreased sex drive…or Have trouble losing weight.
If you have hypothyroidism, the main treatment is to use a synthetic form of T4 hormone- called Levothyroxine that simply replaces what your body isn't producing. After starting hormone replacement, your hormone levels should be checked about every 6 weeks, to make sure you are maintaining normal levels.
It's important to remember that treating hypothyroidism does not cure the problem, it only controls it. And once you're on Thyroid hormone replacement, you're probably on it for life. The good news is that once your thyroid situation is properly regulated, you'll probably feel a whole lot better.
Reviewed ByReview Date: 10/25/2011
Alan Greene, MD, Author and Practicing Pediatrician; also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
Hypothyroidism. (or congenital hypothyroidism)
pathophysiology of anemia in hypothyroidism
Hypothyroidism does not cause mental "retardation". MR is caused by genetics usually. Hypothyroidism is treatable.
Hypothyroidism is a lack of iodine or a specific kind of salt.
Hypothyroidism is a medical condition and not a diet. Hypothyroidism prevents people from losing weight. Therefore on average people do not lose weight if they have hypothyroidism.
Hypothyroidism causes you to retain water that leads to bloating.
William Gull was the first to mention hypothyroidism in a speech given in 1874. The first treatment for hypothyroidism was discovered in 1891 by George Murray.
I was always cold and tired, and a blood test showed that I had hypothyroidism.
Yes. I have hypothyroidism and i look 9 mos pregnant now! :(
Dwarfism is zinc deficiency. hypothyroidism is iodine deficiency.
Myxedema is adult hypothyroidism whereas cretinism is neonatal hypothyroidism.
Suggest a diet for hypothyroidism patient with chronic heart disease.