How to recognise and treat heat exhaustion

Learn the symptoms and treatments for heat exhaustion, heat stroke, cramps and heat rash.

Extreme heat isn’t just uncomfortable, it can also be deadly if you don’t look after yourself and your loved ones. When the temperature heats up, the most at-risk are those over 65, children, pregnant or nursing mothers, those with certain medical conditions and people on medication for mental illness.

The greatest treatment is prevention. On hot days stay out of the sun if you can, cover up with protective clothing, sunglasses and sunblock if you can’t, stay cool and drink plenty of water to remain hydrated. 

Here’s how to recognise and treat some of the heat related illnesses. 

Heat rash 

This condition is most common in children but it can happen to anyone. Heat rash is a skin irritation which is caused by excess sweating and looks like a cluster of small red blisters or pimples. You’re most likely to find it on the chest, neck, groin area, under the breasts or in the elbow creases. 
  • Dry the affected area 
  • Move to a cooler, less humid space
  • Avoid creams or ointments as they keep the skin moist and warm and could make it worse
  • Try unscented talcum powder on the affected area
  • Seek medical attention if it doesn’t improve.

Heat exhaustion

This is a serious medical condition which, if not managed, can develop into heatstroke. Heat exhaustion is caused by sweating excessively in hot conditions, which leads to a drop in a person’s blood volume. 

Warning signs can include rapid heart rate, headaches, appearing pale and sweating, muscle cramps (see above), nausea and vomiting, fainting or dizziness. 

  • Move the person to a cool area in the shade to lie down 
  • Remove any excess unnecessary clothing and wet their skin or clothes with water
  • Drink water if they’re fully conscious
  • Seek medical attention
Girl cooling down in front of a fan

Heat Stroke

If a person has heatstroke it is a medical emergency which requires immediate action. Heatstroke occurs when a person’s temperature rises above 40.5 degrees Celsius and their internal systems start shutting down 

  • Call 000 and request an ambulance
  • Move the person to a cool area in the shade to lie down 
  • If a person is unconscious, position them on their side and keep their airways clear
  • Do not give them anything to drink while you’re waiting for an ambulance to arrive unless instructed otherwise by a medical professional 
  • Remove their clothes and cool their skin with water
  • If the ambulance is delayed, ask for instructions from the 000 operator or staff at a hospital emergency department. 


Cramps can happen after intense physical activity in the heat when the body loses too much water and salt. They can include muscle pains or spasms, which are most common in the legs, arms, or abdomen. Cramps can also be a sign of heat exhaustion.

  • Stop whatever physical activity you were doing an rest in a cool shaded place
  • Drink water
  • Rest for a few hours before exercising again
  • Seek medical help if it doesn’t improve

Fainting or dizziness 

This can happen as a result of reduced blood flow to the brain. When a person faints, it’s a short period of unconsciousness often caused by a drop in blood pressure. In extreme heat, blood is pushed away from the main system and into the skin, which is why people often look red in the face when they’re hot. But this can cause a sudden drop in blood pressure which can  cause light headedness, or fainting.

  • Move to a cool area and lie down
  • Drink water
  • Seek help from a doctor if the person’s condition doesn’t improve. 
Important numbers:

In a medical emergency: 000
For phone health advice (24 hrs):  Nurse on call 1300 60 60 24 
For advice on the health of children or babies (24hrs): Maternal and child health line 132 229

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