Thyroid Disease Hyperthyroidism An Overview of Thyroid Storm This life-threatening condition requires immediate medical attention By Mary Shomon Mary Shomon Verywell Health's Facebook Verywell Health's LinkedIn Verywell Health's Twitter Mary Shomon is a writer and hormonal health and thyroid advocate. She is the author of "The Thyroid Diet Revolution." Learn about our editorial process Updated on January 27, 2023 Medically reviewed by Ana Maria Kausel, MD Medically reviewed by Ana Maria Kausel, MD Verywell Health's Facebook Verywell Health's Twitter Ana Maria Kausel, MD, is a double board-certified endocrinologist affiliated with Mount Sinai St. Luke's/Mount Sinai West in New York City. Learn about our Medical Expert Board Fact checked by Zerah Isaacs Fact checked by Zerah Isaacs Zerah Isaacs is a technical research assistant with experience in both academic and industry biomedical research. Learn about our editorial process Print Table of Contents View All Table of Contents Symptoms Causes and Risk Factors Diagnosis Treatment A thyroid storm is a rare but dangerous and potentially life-threatening condition where the thyroid gland produces extremely high levels of thyroid hormone. It's most often due to an existing hyperthyroidism (overactive thyroid) disorder like the autoimmune condition called Graves' disease. Other factors, like infection, also may contribute to the risk. Symptoms of a thyroid storm include uncontrolled hypertension (high blood pressure), a racing heart rate, and a high body temperature. Irregular heart rhythms and digestive system changes, like diarrhea or jaundice, also may be present. This article explains thyroid storm symptoms, causes, and risk factors. It discusses how a thyroid storm is diagnosed and why aggressive treatment is necessary to try to prevent the worst outcomes. Verywell / Laura Porter Symptoms of Thyroid Storm Symptoms of thyroid storm are usually quite extreme and include: A very high fever of 100 to 106 degrees A very high heart rate, which can be as high as 200 beats per minute (BPM) Palpitations, chest pain, and shortness of breath High blood pressure Confusion, delirium, and even psychosis Extreme physical and muscle weakness Extreme fatigue and exhaustion Extreme restlessness, nervousness, and mood swings Exaggerated reflexes, especially in knee and ankle areas Nausea, vomiting, and diarrhea Profuse sweating or dehydration Stupor or coma Recent dramatic weight loss Complications of thyroid storm include stroke and heart attack, which can lead to death. When to Go to the ER Whenever thyroid storm is suspected, you must go to the emergency room immediately. Thyroid storm requires immediate treatment, as it is life-threatening and can develop and worsen quickly. Causes and Risk Factors The primary risk factor for thyroid storm is an underlying hyperthyroidism, such as with untreated Graves' disease. There's also evidence to suggest that a thyroid storm can occur with an Epstein-Barr virus infection and in people diagnosed with COVID-19. Even when the underlying disease is identified and being treated, there are a number of other factors that raise your risk of thyroid storm: Infection, specifically lung infections, throat infections, or pneumonia Recent surgery on your thyroid gland or trauma to your thyroid Abrupt withdrawal of your antithyroid medications Radioactive iodine (RAI) treatment of your thyroid Excessive palpation (handling/manipulation) of your thyroid gland Exposure to a large quantity of iodine (such as an iodine-based contrast agent or the heart drug amiodarone) Severe emotional stress An overdose of thyroid hormone drugs Toxemia of pregnancy and labor In rare cases, even an aspirin overdose can lead to a thyroid storm. What Happens to Cause a Thyroid Storm? With thyroid storms, the thyroid usually produces an extreme amount of the key hormones involved in thyroid function—triiodothyronine (T3) and thyroxine (T4). This can cause your heart rate, blood pressure, and body temperature to become uncontrollably high. Causes and Risk Factors of Hyperthyroidism Diagnosing a Thyroid Storm Healthcare providers have developed a scoring system that helps them quickly assess symptoms and make a presumptive diagnosis of thyroid storm, so they can rapidly begin treatment. The system involves measuring: TemperatureHeart rateGastrointestinal symptomsNeurological symptomsWhether the patient has had a previous thyroid storm Sometimes, blood tests are done to look for high levels of thyroid hormones. A TSH (thyroid stimulating hormone) test may also be done. Because thyroid storm is a medical emergency, however, there is rarely time to wait for test results and treatment is started immediately. Thyroid Testing and Diagnosis Thyroid Storm Treatment When treating thyroid storm, healthcare providers typically use multiple interventions meant to interfere with the excessive thyroid hormone levels causing it. Treatment includes: Blocking the synthesis of thyroid hormone using antithyroid drugs. This is typically done right away with larger initial loading doses and frequent administration of additional doses. In patients who can't tolerate antithyroid drugs, lithium is sometimes used. Blocking the release of thyroid hormone using a potassium iodide preparation. This is usually given after the antithyroid drugs. Blocking T4 to T3 conversion using a corticosteroid drug, such as hydrocortisone Use of a beta-blocker drug, such as propranolol, to reduce blood pressure and heart rate Supportive treatment may also include cooling to help reduce body temperature, fluids to combat dehydration, and treatment of any other infections. Typically, if the treatments are going to work, the improvement will be seen within 48 hours. The mortality rate in people whose thyroid storm goes untreated ranges from 80% to 100%. When treated, thyroid storms prove fatal in less than half of cases, with some studies suggesting a rate as low as 10%. When thyroid storm does not respond to these approaches, plasmapheresis, a blood filtering treatment, is sometimes done to remove thyroid hormone from the bloodstream. In rare cases, the thyroid is surgically removed. How to Take Your Thyroid Medication Summary While a thyroid storm is rare, it is life-threatening. The symptoms of rapid heart rate, very high blood pressure, and extremely high body temperature are usually related to an underlying hyperthyroidism such as Graves' disease. A thyroid storm needs to be diagnosed and treated immediately, typically with medications used to block thyroid hormone activity and lower the body's vital signs. If left untreated, 80% or more of thyroid storm cases prove fatal. The potential for an underlying thyroid disorder is one good reason to keep up-to-date on your routine healthcare exams. Your healthcare provider can feel your thyroid to check if it's enlarged (a sign of hyperthyroidism) and order annual blood tests. They can ensure any treatment plan you need is designed to manage thyroid disease. 6 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Ylli D, Klubo-Gwiezdzinska J, Wartofsky L. Thyroid emergencies. Pol Arch Intern Med. 2019;129(7-8):526-534. doi:10.20452/pamw.14876 Idrose AM. Acute and emergency care for thyrotoxicosis and thyroid storm: Management of thyroid storm. Acute Medicine & Surgery. 2015;2(3):147-157. doi:10.1002/ams2.104 Idrose AM. Acute and emergency care for thyrotoxicosis and thyroid storm. Acute Med Surg. 2015;2(3):147-157. doi:10.1002/ams2.104 Albehair MA, Alagga AA, Ghulam WZ, Alomair AM, AlFaraj D. Thyroid Storm: Unusual Presentation and Complication. Cureus. 2021 Jan 4;13(1):e12483. doi:10.7759/cureus.12483 Lania A, Sandri MT, Cellini M, Mirani M, Lavezzi E, Mazziotti G. Thyrotoxicosis in patients with COVID-19: the THYRCOV study. Eur J Endocrinol. 2020 Oct;183(4):381-387. doi:10.1530/EJE-20-0335 Tengku Ibrahim TZ, Thambiah SC, Samsudin IN, Nasuruddin AN, Zakaria MH. Thyroid storm: Is there a role for thyroid function test? Malays J Pathol. 2019;41(3):355-358. By Mary Shomon Mary Shomon is a writer and hormonal health and thyroid advocate. She is the author of "The Thyroid Diet Revolution." See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit