Thyroid Storm

Thyroid storm is a rare and life-threatening condition that can affect people with hyperthyroidism. Common symptoms include having a high fever and a rapid heart rate. Thyroid storm is a medical emergency and needs to be treated in a hospital.


What is thyroid storm?

Thyroid storm (also called thyroid crisis and thyrotoxic crisis) happens when your thyroid gland releases a large amount of thyroid hormone in a short amount of time. It’s a rare complication of hyperthyroidism. Thyroid storm is a medical emergency and is life-threatening.


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What does my thyroid do?

Your thyroid is a butterfly-shaped gland located in the front of your neck. Glands are organs that create and release hormones — substances that help your body function and grow. Your thyroid gland plays a large role in many important bodily functions.

Your thyroid gland produces and releases two hormones called triiodothyronine (also called T3) and thyroxine (also called T4). Together, they are referred to as thyroid hormones, and they regulate your body temperature and control your heart rate and metabolism.

Metabolism is the pace at which your body processes things — how fast it burns food to make energy and heat. When you have thyroid storm, the large level of thyroid hormones in your body launches your metabolism into high speed, which is dangerous and life-threatening. When there’s intense metabolic activity, your body needs more oxygen. To meet your body’s oxygen needs, your heart beats very fast (tachycardia), which can cause heart failure.

Who gets thyroid storm?

Thyroid storm is a complication of hyperthyroidism, so people who have conditions that cause hyperthyroidism, such as Graves’ disease or a toxic thyroid adenoma, are more likely to get thyroid storm. Just like with all thyroid disorders, women and people assigned female at birth are more likely to experience thyroid storms than men or people assigned male at birth. The average age of a person who gets thyroid storm is 42 to 43 years.


How common is thyroid storm?

Thyroid storms are rare. Approximately 5 to 7 people per 1 million people in the United States experience thyroid storm.

What does thyroid storm feel like?

Since thyroid hormone affects many parts of your body, if you’re experiencing thyroid storm, you’ll likely feel pretty bad all over. You may feel:

  • Very hot and sweaty.
  • Like your heart is going to beat out of your chest.
  • Very agitated or anxious.
  • Shaky.
  • Sick to your stomach.
  • Like you don’t have control of your body.
  • Confused.

It’s essential to get to the nearest hospital as soon as possible if you’re experiencing any of these symptoms.


Symptoms and Causes

Symptoms of thyroid storm include high fever, agitation, delirium and congestive heart failure. Seek immediate medical attention.
Thyroid storm happens when your thyroid makes and releases a large amount of thyroid hormone in a short amount of time. It's a life-threatening condition.

What causes thyroid storm?

Researchers aren’t yet sure why certain factors can result in thyroid storms. Although thyroid storm can develop if you have long-term untreated or undertreated hyperthyroidism, it’s often caused by a sudden and intense (acute) event or situation.

Sudden events that can trigger a thyroid storm include:

  • Suddenly stop taking your antithyroid medication.
  • Thyroid surgery (thyroidectomy).
  • Nonthyroid surgery.
  • Trauma.
  • Infection.
  • Acute illnesses such as diabetic ketoacidosis (DKA), heart failure and a drug reaction.
  • A sudden large amount of iodine in your body, such as from an iodinated contrast agent that’s used for certain imaging procedures.
  • Giving birth.
  • Stroke.

What are the signs and symptoms of thyroid storm?

Common signs and symptoms of thyroid storm include:

  • Having a high fever — a temperature between 104 degrees to 106 degrees Fahrenheit is common.
  • Having a rapid heart rate (tachycardia) that can exceed 140 beats per minute.
  • Feeling agitated, irritable and/or anxious.
  • Delirium.
  • Congestive heart failure.
  • Loss of consciousness.

Less common signs and symptoms of thyroid storm include:

  • Severe nausea and/or vomiting.
  • Diarrhea.
  • Abdominal pain.
  • Yellowing skin or eyes (jaundice).

Diagnosis and Tests

How is thyroid storm diagnosed?

A healthcare provider diagnoses thyroid storm if the person has severe and life-threatening symptoms, such as extreme fever and heart issues, and high levels of thyroid hormone and low levels of thyroid-stimulating hormone (TSH) in their blood.

Since thyroid storm can be life-threatening and requires immediate medical attention, in many cases, healthcare providers diagnose and start treating people who have signs of thyroid storm before they get blood results back indicating the level of thyroid hormones in their blood.

Healthcare providers may also rely on a physical examination to check for physical signs of thyroid storm, including:

  • Goiter, which is when your thyroid gland is enlarged.
  • Ophthalmopathy, which is a complication of Graves’ disease that involves eye issues such as swelling and bulging eyes.
  • Lid lag, which is when your upper eyelid is higher than it should be when you’re looking down.
  • Hand tremors.
  • Warm and moist skin.
  • Tachycardia or atrial fibrillation.

Management and Treatment

How is thyroid storm treated?

Since thyroid storm is a medical emergency, you’ll need to be treated for it in a hospital. If you’re experiencing symptoms, get to the nearest hospital as soon as possible.

The treatment strategy for thyroid storm can be divided into four general categories, including:

  • Treatment targeted against thyroid hormone creation and release.
  • Treating your body systems and tissues, such as your heart, that are affected by the excess thyroid hormone.
  • Treatment of the situation or illness that caused your thyroid storm.
  • Other supportive treatments to help with symptoms and side effects.

Medications and treatment therapies for thyroid storm can include:

  • Antithyroid medication (thionamides) to stop your thyroid from making new thyroid hormones.
  • Iodine solution to stop your thyroid from releasing thyroid hormone.
  • Beta-blockers to manage your symptoms.
  • Bile acid sequestrants to prevent your gut from reabsorbing thyroid hormone.
  • Acetaminophen and cooling blankets to lower your temperature.
  • Respiratory treatment, such as supplemental oxygen.

If you have thyroid storm, you’ll likely be in the intensive care unit (ICU) of the hospital so your healthcare team can monitor your symptoms and condition frequently.

How soon will I feel better after treatment for thyroid storm?

With the proper medical treatment, you’ll likely feel better within 24 hours. It could take up to a week to treat what caused your thyroid storm.


Can I prevent thyroid storm?

Not all cases of thyroid storm are preventable, but if you have hyperthyroidism, there are things you can do to try to prevent thyroid storm, including:

  • Always taking your medication as prescribed by your healthcare provider.
  • Seeing your healthcare provider regularly to make sure your treatment is working.
  • Managing your stress.

Thyroid storm can be caused by your body’s stress response to surgery or anesthesia. Because of this, your healthcare provider may give you antithyroid medication before you have surgery to try to prevent thyroid storm.

If you have hyperthyroidism and are having thyroid surgery (thyroidectomy), your provider will most likely give you certain medication before the surgery to try to prevent thyroid storm.

Outlook / Prognosis

What is the prognosis (outlook) for thyroid storm?

Thyroid storm is a medical emergency that is fatal if it’s not treated. Causes of death from thyroid storm can be heart failure, heart arrhythmias (abnormal heartbeats) or multiple organ failure. However, with treatment, most people experience improvement within 24 hours.

Risk factors for poor prognosis include:

  • If you’re of advanced age.
  • Having neurological issues upon admission to a hospital, such as decreased sensation and mental function issues.
  • If your healthcare provider is unable to use beta-blockers and antithyroid medications to treat your thyroid storm due to other health conditions.
  • If you need dialysis and/or mechanical ventilation (when a machine breathes for you) due to thyroid storm.

Can thyroid storm be fatal?

Thyroid storm is a life-threatening medical condition that is fatal if it’s not treated. Even with treatment, it can be fatal. Approximately 10% to 30% of thyroid storm cases result in death.

It’s essential to get to the hospital as soon as possible if you’re experiencing symptoms of thyroid storm. Don’t wait for your symptoms to get worse.

What are the complications of thyroid storm?

Thyroid storm can lead to serious complications if treatment is delayed or if it’s untreated, including:

Living With

When should I go to the emergency room?

If you’re experiencing symptoms of thyroid storm such as a high fever and a rapid heart rate, get to the nearest emergency room as soon as possible.

A note from Cleveland Clinic

Thyroid storm is a serious and life-threatening medical condition. Luckily, it’s rare and treatable. If you’re experiencing symptoms of thyroid storm, such as a high fever and a fast heart rate, get to the nearest hospital immediately. If you have hyperthyroidism, such as Graves’ disease, ask your healthcare provider about thyroid storm and how you can try to prevent it from happening to you.

Medically Reviewed

Last reviewed on 06/08/2022.

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