Heat exhaustion is one of the heat-related syndromes, which range in severity from mild heat cramps to heat exhaustion to potentially life-threatening heatstroke.
Signs and symptoms of heat exhaustion often begin suddenly, sometimes after excessive exercise, heavy perspiration, and inadequate fluid or salt intake. Signs and symptoms resemble those of shock and may include:
- Feeling faint or dizzy
- Nausea
- Heavy sweating
- Rapid, weak heartbeat
- Low blood pressure
- Cool, moist, pale skin
- Low-grade fever
- Heat cramps
- Headache
- Fatigue
- Dark-colored urine
If you suspect heat exhaustion:
- Get the person out of the sun and into a shady or air-conditioned location.
- Lay the person down and elevate the legs and feet slightly.
- Loosen or remove the person's clothing.
- Have the person drink cool water or other nonalcoholic beverage without caffeine.
- Cool the person by spraying or sponging with cool water and fanning.
- Monitor the person carefully. Heat exhaustion can quickly become heatstroke.
Call 911 or emergency medical help if the person's condition deteriorates, especially if fainting, confusion or seizures occur, or if fever of 104 F (40 C) or greater occurs with other symptoms.
- What to do in a medical emergency: Heat-related illnesses. American College of Emergency Physicians. http://www.emergencycareforyou.org/EmergencyManual/WhatToDoInMedicalEmergency/Default.aspx?id=254&terms=heat+exhaustion. Accessed Feb. 23, 2012.
- Ishimine P. Heat illness (other than heat stroke) in children. http://www.uptodate.com/index. Accessed Feb. 23, 2012.
- Heat stress. Centers for Disease Control and Prevention. http://www.cdc.gov/niosh/topics/heatstress. Accessed Feb. 23, 2012.
- Ferri FF. Ferri's Clinical Advisor 2012: 5 Books in 1. Philadelphia, Pa.: Mosby Elsevier; 2012. http://www.mdconsult.com/books/about.do?about=true&eid=4-u1.0-B978-0-323-05611-3..C2009-0-38601-8--TOP&isbn=978-0-323-05611-3&uniqId=291436269-101. Accessed Feb. 23, 2012.
- Meloy TD (expert opinion). Mayo Clinic, Rochester, Minn. Feb. 24, 2012.


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