Heat exhaustion: learn first aid

First aid advice for someone with heat exhaustion. Find out the symptoms, how to spot the early signs, and what treatment they may need in an emergency.

What is heat exhaustion?

Heat exhaustion happens when the body gets too hot, usually during a heatwave or in hot temperatures. Someone with heat exhaustion might have been in the sun or heat for a long time. They might look ashen, have a headache or dizziness, and feel sick.

Signs and symptoms of heat exhaustion

  • If you think someone has heat exhaustion, they may show the following signs or symptoms:
  • dizzy or confused and complaining of headaches or cramps
  • sweating, with cooler skin to the touch
  • paler than usual - depending on your skin tone, this could mean your skin looks ashen, grey or a more yellowish hue. It might be easier to notice this change in colour on the palms of hands, nails, eyes, gums or tongue feel nauseous, with fast breathing and heart rate.

A child or baby with heat exhaustion might have been in the sun or heat for a long time. They might be sweating, have ashen, cool skin, have a headache or dizziness, and feel sick.

Learn heat-related first aid treatment for babies and children.

First aid treatment for someone who has heat exhaustion

Step 1. Help them to a cool place and get them to rest

Heat exhaustion happens when someone loses too much fluid and salt usually from sweating in hot conditions.

Step 2. Give them plenty of water to drink

Drinking water will replace lost fluids. If you have them, isotonic sports drinks will help replace salts lost through sweating.

Step 3. Seek medical advice

Even if the person appears to recover fully, you should seek medical advice. If their condition gets worse, call 999 for emergency help.

Watch Laura’s story to learn first aid for heat exhaustion

(3 minutes 21 seconds)

Laura's story will help you learn about the symptoms of heat exhaustion and what to do next when you notice someone might be suffering from the heat. Skip to 1:04 for the key first aid steps.

More basic first aid learning for heat exhaustion

Heat exhaustion is a heat-related illness closely related to other first aid emergencies. Keep yourself and others safe during hot weather and: