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Heatstroke and heat exhaustion

Heatwaves and hot weather can kill. Learn about the signs, symptoms and treatment of heatstroke and heat exhaustion so you can help yourself and others when the temperature soars.

Lady re-hydrating with a bottle of water

During heatwaves or extremely hot weather, it's easy to become dehydrated or for your body to overheat. If this happens, you may develop heat cramps, heat exhaustion or even heatstroke, which is a life-threatening condition.

The heat can affect anyone, but some people are more at risk because their body doesn't regulate heat well, including:

  • older people.
  • babies and young children.
  • people with mental-health conditions.
  • people on certain medications.
  • people with chronic conditions (such as breathing or heart problems).
  • people with limited mobility.

Heatwaves can kill, so learn how to stay cool in hot weather and watch for the signs and symptoms of heat exhaustion and heat stroke. Here's what to look for and what you can do to help.

What is heat exhaustion?

Heat exhaustion happens when someone becomes dehydrated due to loss of water from exercising or working in poorly ventilated conditions.

  • Heat exhaustion signs and symptoms
  • Muscle cramps, especially in the calves and toes.
  • Exhaustion and general weakness.
  • Nausea and/or vomiting.
  • Dizzy spells.
  • Pale, cool, clammy skin at first, becoming flushed and red later.
  • A rapid, weak pulse and rapid, noisy breathing.

Heat exhaustion treatment

  • Help the person to lie down at total rest in a cool area.
  • Loosen any tight clothing.
  • If fully alert and conscious, give them frequent small drinks of water or ice chips to suck.
  • If muscle cramps occur, gently stretch the affected muscles to ease pain.
  • Check vital signs at regular intervals.
  • If unconscious or not fully conscious, place in the recovery position.
  • If the person is unable to drink, or is vomiting or unconscious, call 000 for an ambulance (or 112 from a mobile).
  • Prepare to give CPR if necessary.

What is heat stroke?

Heat stroke is a life-threatening emergency and can cause a person to collapse or fall unconscious Heat stroke is more serious and means the body is no longer able to regulate its temperature by cooling the skin's surface by sweating. The internal body temperature rises, and organ damage can occur.

Heat stroke signs and symptoms

  • No longer sweating.
  • Red, hot and dry skin.
  • A body temperature over 40°C.
  • A rapid, strong pulse.
  • Rapid, noisy breathing.
  • Irrational or aggressive behaviour.
  • Deterioration of the conscious state.

Heat stroke treatment

  • Call 000 for an ambulance immediately (or 112 from a mobile).
  • Cool the person using wet towels or a wet sheet with a fan directed across the surface.
  • If ice packs are available, wrap them in towels and place them in the armpits or groin.
  • If shivering occurs stop active cooling.
  • Check vital signs at regular intervals.
  • If unconscious or not fully conscious, place in the recovery position.
  • Prepare to give CPR if necessary.

Are you ready?

There are simple and practical steps you can take to protect yourself, the people you love, and the things you value most. Do one simple thing to make you safer.

Get prepared