If this is an emergency, please call 000 immediately.

What is heat exhaustion?

If a person with heat exhaustion is not managed appropriately, they can develop heat stroke.

It is very important that a person’s body temperature stays in the range of 36.1 – 37.8°C. If body temperature rises above this, a person may develop heat-related illness. When the weather is very hot, the body has to work very hard and produce a lot of sweat to keep itself cool. It is more difficult for a person to sweat if it is humid, or if the person is already dehydrated.

This guide is regularly updated and aligns with the current edition of Australian First Aid (4th edition, 7/2011)

Signs and Symptoms


      • Feeling hot, exhausted, weak, fatigued
      • Persistent headache
      • Thirst
      • Nausea
      • Faintness, dizziness
      • Rapid breathing, shortness of breath
      • Pale, cool, moist skin
      • Rapid, weak pulse


What to do

Move the patient to a cool place with circulating air.



Help the patient to sit or lie down in a comfortable position.


Remove unnecessary clothing from the patient, and loosen any tight clothing.


Sponge the patient with cold water.


Give the patient cool water to drink.


Seek medical aid if the patient vomits or does not recover quickly.



Heat exhaustion fact sheet

DRSABCD poster

Related advice

Heat stroke

Heat stroke is potentially life-threatening and immediate medical aid is needed.

Smoke and embers in your eyes

Exposure to smoke and harmful or poisonous gases and chemicals can lead to eye irritation, pain and discomfort. Here’s how to treat smoke or embers in your eyes.

Asthma attack

Most people who experience asthma attacks should have an action plan and medication with them at all times. Here is a fact sheet of what to do if someone has an asthma attack.

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