Heat-related illness signs, symptoms and treatment

In very hot weather, you can get burnt from contact with the hot ground in seconds. If someone has collapsed outdoors, try to place something between them and the hot ground (like a towel or blanket) to prevent burns, or if safe to do so, move them into the shade or onto the grass. 


Early signs of dehydration and heat-related illness include:

  • sweating heavily
  • having a raised body temperature
  • feeling dizzy or faint
  • feeling tired and lethargic
  • reduced appetite
  • feeling thirsty
  • being irritable
  • twitching or having painful muscle cramps in the arms, legs or abdomen.

Heat exhaustion

Heat exhaustion is the body’s response to an excessive loss of water and/or salt contained in sweat. It results from exposure to high heat or strenuous physical exercise.

The signs and symptoms of heat exhaustion include:

  • headaches
  • having a raised body temperature
  • sweating heavily
  • fatigue, weakness, and restlessness
  • nausea and vomiting
  • weak, rapid pulse
  • poor coordination
  • anxiety.

What to do if you or someone you know is showing the signs of heat exhaustion:

  • stop what you are doing, go to a cool, shaded place and lie down with legs supported and slightly lifted
  • slowly sip plenty of water or fruit juice, avoiding caffeine and alcohol
  • cool down with a fan or an air-conditioner, cool water sprayed on skin or by having a cool shower or bath
  • reduce body temperature by placing cool packs under the armpits, groin, or neck
  • use massage to ease spasms or cramps, then use ice packs.

If symptoms of heat exhaustion last for more than an hour, call Triple Zero (000) immediately for an ambulance or go to a hospital Emergency Department.

Heatstroke

Heatstroke is a severe illness where a person’s temperature is greater than 40°C, resulting from exposure to high heat or strenuous physical exercise.

The signs and symptoms of heatstroke include:

  • headache, dizziness, nausea, vomiting and confusion
  • having flushed, hot and unusually dry skin
  • being extremely thirsty
  • having a dry, swollen tongue
  • having a sudden rise in body temperature to more than 40°C
  • being disoriented or delirious
  • slurred speech
  • being aggressive or behaving strangely
  • convulsions, seizures or coma.
  • may be sweating and skin may feel deceptively cool
  • rapid pulse.

If you notice any of the above signs of heatstroke in yourself or others, call Triple Zero (000) immediately for an ambulance.

Heatstroke is an extreme medical emergency. If not treated immediately, it can lead to permanent damage to vital organs or even death.

While waiting for the ambulance to arrive:

  • move the person to somewhere cool and keep them still if possible
  • do not give aspirin or paracetamol to a person affected by heat

If the person is conscious:

  • move them to a cool area and keep them still
  • give them small sips of fluid
  • bring their temperature down using any method available
  • loosen their clothes, sprinkle them with cool water, or wrap them in a damp sheet
  • place cool, damp cloths in their armpits, on the back of their neck and on their forehead to cool them down as quickly as possible
  • use a fan to help cool them down if one is available
  • do not give them aspirin or paracetamol.

If the person is unconscious:

  • move the person to somewhere cool and keep them still if possible
  • lay them on their side (recovery position) and check they can breathe properly
  • perform CPR if needed
  • do not give aspirin or paracetamol to a person affected by heat.
  • stay with them until the ambulance arrives.

See the Know the signs of heat exhaustion and heat stroke factsheet (PDF 205KB).



In this section