How Hyperthermia Works

Malignant Hyperthermia
People with malignant hyperthermia have a severe reaction to certain anesthetics.
People with malignant hyperthermia have a severe reaction to certain anesthetics.

While hyperthermia is a symptom indicative of some other problem like heat stroke, malignant hyperthermia is another story. Malignant hyperthermia is an inherited condition. Only one parent has to carry the gene for malignant hyperthermia for a child to inherit it. Doctors can look for signs that someone has malignant hyperthermia by looking for damage in the RYR1 gene [source: U.S. National Library of Medicine].

People with malignant hyperthermia react poorly to some types of anesthesia. A common symptom is a rapid increase in body temperature. Other symptoms can include bleeding, muscle pains or tightness, and the patient's urine turning a dark brown color. People with malignant hyperthermia may also have other muscular diseases.

Malignant hyperthermia is a serious condition and can be life threatening if the patient requires surgery. Often, the first time patients discover they have malignant hyperthermia is when they are given anesthesia. A severe reaction may include an irregular heartbeat.and may cause the patient's kidneys to shut down.

Doctors can use drugs to help regulate the patient's heartbeat and keep the kidneys operating. They can also use special cooling blankets to help manage the patient's body temperature. If the doctors know ahead of time about the condition, they can use anesthetics that don't trigger malignant hyperthermia reactions. The U.S. National Library of Medicine recommends that people with a family history of malignant hyperthermia seek out genetic counseling.

People with malignant hyperthermia can lead normal lives. They can be blood or organ donors. The Malignant Hyperthermia Association of the United States (MHAUS) recommends that adults with malignant hyperthermia wear medical ID tags to let emergency medical technicians know about the condition. A person with malignant hyperthermia has a 50-percent chance to pass it on to his or her child (assuming the other parent doesn't have malignant hyperthermia). Because of that, MHAUS recommends that parents with malignant hyperthermia get a medical ID bracelet for their children.

Medicine has made great progress in identifying and treating people with malignant hyperthermia. According to the Orphanet Journal of Rare Diseases, the mortality rate for patients with malignant hyperthermia dropped from 80 percent to just 5 percent over the last 30 years [source: OJRD].

Learn more about health conditions and how to manage them by following the links below.

Related Articles


  • American Cancer Soceity. "Hyperthermia." (Sept. 30, 2010)
  • Doerr, Steven. "Hyperthermia and Heat-Related Illnesses." (Sept. 30, 2010)
  • Duke University School of Medicine. "Hyperthermia Treatment." 2007. (Sept. 30, 2010)
  • Heller, Jacob L. and Zieve, David. "Malignant hyperthermia." U.S. National Library of Medicine. July 8, 2009. (Sept. 29, 2010) Kaneshiro, Neil K. and Zieve, David. "Fever." U.S. National Library of Medicine. Jan 29, 2009. (Sept. 29, 2010)
  • Malignant Hyperthermia Association of the United States. "MH Susceptible Patient FAQs." February 2005. (Sept. 29, 2010)
  • Mayo Clinic. "Diuretics." Dec. 17, 2008. (Sept. 30, 2010)
  • National Cancer Institute. "Hyperthermia in Cancer Treatment: Questions and Answers." Aug. 12, 2004. (Sept. 30, 2010)
  • National Cancer Institute. "Metastatic Cancer : Questions and Answers." Sept. 1, 2004. (Sept. 30, 2010)
  • National Institute on Aging. "Hyperthermia: Too Hot for Your Health." Sept. 16, 2010. (Sept. 30, 2010)
  • Rosenberg, Henry, et al. "Malignant hyperthermia." Orphanet Journal of Rare Diseases. April 24, 2007. (Sept. 29, 2010)
  • Tunkel, Allan R. "Defenses Against Infection." The Merck Manuals. October 2008. (Sept. 30, 2010)
  • Vorvick, Linda and Zieve, David. "Body temperature normals." U.S. National Library of Medicine. Feb. 1, 2009. (Sept. 29, 2010)

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