Myxedema is a severe form of hypothyroidism characterized by swelling and thickening of your skin. More severe symptoms, such as hypothermia or shock, could indicate a myxedema crisis requiring immediate medical attention.

Myxedema is another term for severely advanced hypothyroidism. It’s a condition that occurs when your body doesn’t produce enough thyroid hormone.

The thyroid is a small gland that sits right at the front of your neck. It releases hormones that help your body regulate energy and control a wide variety of functions. Myxedema is the result of having undiagnosed or untreated severe hypothyroidism.

The term “myxedema” can mean severely advanced hypothyroidism. But it’s also used to describe skin changes in someone with severely advanced hypothyroidism. The classic skin changes are:

  • swelling of your face, which can include your lips, eyelids, and tongue
  • swelling and thickening of skin anywhere on your body, especially in your lower legs

Severely advanced hypothyroidism can lead to what’s called a myxedema crisis, which is a medical emergency. While the term “myxedema coma” is used to describe this life-threatening situation, “myxedema crisis” has replaced it, as a comatose state is no longer required to diagnose the condition.

Read on to learn more.

In addition to skin changes, other signs and symptoms of severe hypothyroidism can include:

  • low systolic and high diastolic blood pressure
  • low heart rate
  • sparse or brittle hair
  • cold intolerance
  • goiter (enlargement of the thyroid gland)
  • low energy and lethargy
  • weight gain
  • weakness
  • cold intolerance
  • constipation
  • depressed mood

Myxedema crisis occurs when your body can no longer tolerate the changes caused by severe hypothyroidism, so it decompensates. This is a life-threatening state that requires immediate medical attention. Along with the signs and symptoms of severe hypothyroidism, symptoms of myxedema crisis can include:

  • decreased breathing (respiratory depression)
  • lower than normal blood sodium levels
  • hypothermia (low body temperature)
  • confusion or mental slowness
  • shock
  • low blood oxygen levels
  • high blood carbon dioxide levels
  • coma
  • seizures

Myxedema crisis can cause death often due to complications from infection, bleeding, or respiratory failure. It’s more common in women and people over the age of 60. It can occur during pregnancy as well.

Hypothyroidism occurs when the thyroid stops functioning correctly. This may be caused by:

Myxedema is a result of undiagnosed or untreated severe hypothyroidism. It can also develop when someone stops taking their thyroid medication. It’s more common in the elderly and women.

Deposits of chains of sugar molecules in the skin cause the skin condition myxedema. These compounds attract water, which leads to swelling. These skin changes are a result of hypothyroidism.

Myxedema crisis often occurs after a long history of hypothyroidism. It’s more common during cold winter months. Any of the following can trigger it:

  • stopping hypothyroid treatment medication
  • sudden illness, like heart attack or stroke
  • infection
  • trauma
  • certain drugs that suppress the central nervous system
  • exposure to cold
  • stress

Your symptoms will lead your doctor to suspect severe hypothyroidism. Blood tests can help your doctor confirm this.

A thyroid-stimulating hormone (TSH) test measures how much TSH your pituitary gland produces. Your pituitary gland will increase TSH production if your thyroid isn’t producing enough. In other words, a high level of TSH could mean you have hypothyroidism.

A TSH test is typically checked along with a thyroxine (T4) test. This test measures the level of T4, a hormone produced directly by your thyroid. If you have low levels of T4 coupled with a high level of TSH, you have hypothyroidism.

Your doctor will likely want to perform more tests to determine your thyroid function and other conditions that may be affecting it.

Myxedema crisis is a medical emergency. Once suspected, TSH and T4 levels need to be checked right away. Treatment can begin as soon as possible. The initial diagnosis often relies on the physical examination.

Emergency medical personnel will look out for other features of severe hypothyroidism like:

  • dry skin
  • sparse hair
  • hypothermia
  • swelling, especially in your face and legs
  • goiter
  • a possible surgical scar from a thyroidectomy
  • low blood pressure and heart rate
  • confusion
  • decreased breathing

You’ll start to receive thyroid hormone replacement therapy if your doctor suspects a myxedema crisis. The preferred route is through a vein using an intravenous line (IV).

Your doctor will order other blood tests to get a thorough picture of your body systems. A CT scan of your brain will likely be needed as well.

Your vital functions and level of consciousness are also continually monitored during this process. You’ll require hospitalization treatment in the intensive care unit (ICU) until you’re stable.

Thyroid hormone is essential for cell metabolism. So severely advanced cases of hypothyroidism can slow down metabolism and affect oxygen use in your body. This can have a negative impact on nearly all bodily processes and body systems. As a result, myxedema can lead to:

Treatment for hypothyroidism involves taking a synthetic version of the T4 hormone, levothyroxine (Levothroid, Levoxyl). Once T4 hormone levels are restored, symptoms become more manageable, though this may take several weeks. You’ll likely have to remain on this medication for the rest of your life.

Myxedema crisis is considered a medical emergency and requires immediate attention. Those undergoing a myxedema crisis need to be treated in an ICU. Their heart and breathing are continually monitored. Along with thyroid hormone replacement, steroid treatments and other medications may be needed.

Without a rapid diagnosis, myxedema crisis is often fatal. The mortality rates may be as high as 25 to 60 percent even with treatment. Older adults are at a higher risk of having a poor outcome.

If not treated, advanced hypothyroidism can lead to severe complications and even death. The outlook for myxedema is good if you receive thyroid replacement therapy. But you will need to continue treatment for the rest of your life. If hypothyroidism is well-controlled, it won’t shorten your life span.