Hyperthermia (cont.)

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Heat Exhaustion

Heat exhaustion is the body's response to an excessive loss of water and salt contained in sweat as a result of engaging in physical activity (work or exercising) in a hot environment. The body temperature may be normal or mildly elevated, but not above 104 F (40 C). It often  occurs in individuals who are not accustomed to working or exercising in the heat. The symptoms may range from minor complaints to more pronounced symptoms, however the affected individual will not experience the central nervous system manifestations noted with heat stroke. Many cases of heat exhaustion can be treated outside of the hospital setting.

What are the signs and symptoms of heat exhaustion?

Warning signs of heat exhaustion include:

  • a normal or mildly elevated body temperature,
  • heavy sweating,
  • pallor (paleness),
  • muscle cramps and muscle pain,
  • fatigue,
  • weakness,
  • dizziness and lightheadedness,
  • headache, and
  • nausea.

The skin may be cool and moist. The affected individual's pulse rate may be fast, and breathing may be fast and shallow. If heat exhaustion is untreated and heat exposure continues, it may sometimes progress to heat stroke.

What is the treatment for heat exhaustion?

Cooling measures that may be effective include:

  • drink cool, non-alcoholic beverages, such as water and sports drinks,
  • eat salty snacks,
  • rest in the shade or in an air-conditioned environment,
  • take a cool shower or bath, and
  • loosen or remove restrictive clothing.

Seek medical attention immediately if:

  • the symptoms are severe or worsening, or
  • the affected individual has serious underlying health problems (for example, heart disease or diabetes).

Otherwise, help the person cool off, and seek medical attention if symptoms worsen or last longer than one hour.

Medically Reviewed by a Doctor on 5/23/2014

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