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Heat Exhaustion

Heat exhaustion occurs when a person can't sweat enough to cool the body. It generally develops when a person is working or exercising in hot weather, sweats a lot, and does not drink enough liquids to replace those lost fluids. Heat exhaustion can be caused by loss of fluid (dehydration) or loss of electrolytes.

Symptoms of heat exhaustion include fatigue, weakness, headache, dizziness, or nausea, and the skin is pale, cool, and moist. Mild heat exhaustion does not cause a decrease in a person's mental alertness, but it may occasionally cause fainting. Mild cases of heat exhaustion usually can be treated at home.

Moderate to severe heat exhaustion can sometimes lead to heatstroke, which requires emergency treatment.

ByHealthwise Staff
Primary Medical ReviewerWilliam H. Blahd, Jr., MD, FACEP - Emergency Medicine
Specialist Medical ReviewerH. Michael O'Connor, MD - Emergency Medicine
Last RevisedSeptember 1, 2011

WebMD Medical Reference from Healthwise

Last Updated: September 01, 2011
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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