Heat stroke

Synonyms: Heat emergencies, Heat illness

Medical Specialties: Emergency medicine, Family practice, Internal medicine

Clinical Definition

Heat stroke is the most severe of three types of heat emergencies, also including heat cramps and heat exhaustion. Heat stroke can cause shock, brain damage, organ failure and death. Fever, irrational behavior and confusion are common.

In Our Own Words

Heat stroke is the most severe form of heat-related illness and can cause shock, brain damage, organ failure and even death. It occurs, as the name implies, when temperatures rise. Heat cramps and heat exhaustion are two other less serious heat emergencies. Symptoms of heat stroke include fever above 104 degrees Fahrenheit, dry and red skin, rapid and shallow breathing and irrational behavior.


Heat stroke can be classic, the effect of heat that can't be escaped, or exertional, striking those who do vigorous exercise in the heat. First aid must be given. The person should lie down in a cool place with feet raised 12 inches. Apply wet, cool cloths to the skin and give fluids until medical help arrives.

Relevant Conditions
  • Hyperthermia
  • Dehydration
Common Types
  • Classic
  • Exertional
Side Effects
  • Confusion
  • High fever
  • Irrational behavior
  • Rapid breathing
  • Seizures
Share this article
  • University of Maryland Medical Center. "Heat emergencies." Medical encyclopedia. January 2012. http://umm.edu/health/medical/ency/articles/heat-emergencies. Accessed November 2013.
  • Harvard Medical School. "Fluids, cool air key to avoiding heat stroke." Harvard Health Publications. July 2013. http://www.health.harvard.edu/blog/fluids-cool-air-key-to-avoiding-heat-stroke-201307056443. Accessed November 2013.
Keep Reading

Investigate your bodys signs and signals.
Try Symptom Checker