Heat Exhaustion: Symptoms, Treatment, & Prevention

Heat Exhaustion: Symptoms, Treatment, & Prevention

When the body becomes dehydrated and is unable to regulate its own body temperature, heat exhaustion can occur.

Heat exhaustion is usually non-life-threatening and can often be treated with fluids and rest. However, without proper intervention, heat exhaustion can progress into a heat stroke, which can damage the brain and other vital organs.

Read on as we look at the symptoms of heat exhaustion, how to treat it, and how to prevent it.


What is Heat Exhaustion?

Generally, our bodies get rid of excess internal heat by pumping blood to the surface of the skin and releasing sweat. Warm, moist air (relative humidity of 60% or more) absorbs less sweat from our skin and limits our bodies ability to cool itself by sweating. The risk of heat exhaustion dramatically increases when the heat index climbs to 90 degrees or more.

When we become dehydrated, our body lacks water and essential salts called electrolytes, which reduces its ability to sweat.  If a person is unable to cool down by sweating, they may experience heat exhaustion.


Symptoms may include:

  • dizziness
  • excessive sweating
  • red flushed face
  • muscle weakness or cramps
  • nausea & vomiting
  • headache
  • rapid pulse rate
  • cold, pale, damp skin, sometimes accompanied by goosebumps
  • light-headedness when standing up or bending over
  • increased internal body temperature
  • rapid, shallow breathing



Perhaps, you or someone you know show signs of heat exhaustion, exercise or physical activity stops immediately.  Hydrate with fluids as soon as possible.


Further tips for treatment may include:

  • look for a shaded area or go indoors
  • loosen your clothes if possible
  • lay down flat on your back
  • immerse yourself in cold water
  • place a cold, wet cloth on your face and chest
  • place ice packs under each armpit and behind the neck
  • drinking 1 liter of fluids containing electrolytes, per hour

If these measures do not help within 15-20 minutes, seek medical attention immediately.

In most cases, a doctor will treat heat exhaustion with one or two liters of intravenous (IV) fluids and electrolytes. If fluids and rest do not resolve the symptoms, a doctor may perform more testing to rule out other potential causes.

Left untreated, heat exhaustion can turn into a heatstroke. If a heat stoke is suspected, call 911 immediately. A heatstroke is extremely dangerous. Without medical attention, it may cause seizures, coma, and can even be life-threatening.

When heat exhaustion is treated promptly, a recovery time of 24-48 hours can be accepted but varies by circumstance and individual.



Prevention is accomplished by taking reasonable precautions for you and your family. The elderly, pregnant women, infants, and children are all more susceptible to heat exhaustion than other individuals because their bodies do not cool as efficiently. Some elderly, children, and infants are dependent on others to manage their environment and to take precautionary measures to avoid heat exhaustion.

It’s important to pay attention to the reported heat index, and also to remember that the heat index is even higher when you are standing in full sunshine.


Prevention tips:

  • avoid hot environments when possible
  • drink fluids during and after exercise
  • avoid outdoor activity and exercising in direct sunlight
  • avoid prolonged exposure to hot, humid weather
  • keeping electrolyte beverages or oral-rehydration salt preparations on hand
  • avoid sugary drinks and sodas
  • do not increase workload or pace too quickly
  • go outside early in the morning or evening
  • increase fluid intake when taking prescribed medications
  • wear lose, lightweight and light-colored clothing

Check with your doctor to see if your health conditions and medications are likely to affect your ability to cope with extreme heat and humidity.


This general information is not intended to diagnose any medical condition or to replace your healthcare professional. If you are displaying very serious signs such as an inability to wake up, seizures, or repeated vomiting, it is a time-sensitive medical emergency and you should seek immediate care and proceed to the emergency room immediately.