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    Heat Exhaustion

    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.

    By Healthwise Staff
    William H. Blahd, Jr., MD, FACEP - Emergency Medicine
    H. Michael O'Connor, MD - Emergency Medicine
    Last Revised August 30, 2013

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