In a nutshell: Heat exhaustion and heatstroke are risks related to hot weather outside but they can affect your child in hot rooms, too. Babies and toddlers are (along with older and more vulnerable people) among those who are most at risk of being affected. An older child can also be affected if they are being very active when the weather is very hot.


Children with heat exhaustion need your help to cool down, so that their body temperature returns to normal. Heat exhaustion can, left untreated, turn into heatstroke (sunstroke): this is a medical emergency and you need to call an ambulance.

What are the signs of heat exhaustion in children?

  • Sweating heavily
  • Tiredness
  • Dizziness
  • Headache
  • Loss of appetite and feeling sick
  • Tummy ache
  • Fast breathing or pulse
  • Cramps in their arms, legs or stomach
  • Temperature of 38°C or above
  • Weeing only small amounts of dark urine

What do I do if my child I think my child has heat exhaustion?

To help your child cool down quickly, you need to:

  • Take them inside, out of the sun
  • Use a fan to cool the room if you have one
  • Take off their clothes
  • Sponge them down with a cool flannel
  • Encourage them to drink plenty of fluids
  • If they are feeling sick, give them fluids little and very often using a syringe – point the syringe between their lower teeth and cheek, so there is less chance of them spitting it out

Usually, doing all these things means your baby or child will start to feel better within about 30 minutes. It they don't or if they become more unwell, get medical advice.

How does heat exhaustion happen?

When the sun is out, children want to be having fun playing outside. We all know that they should be wearing sunscreen, reapplied frequently, as well as a sunhat. But sunburn is not the only health risk from too much sun.

Think back to school biology and you may recall hearing about something called 'homeostasis'. This is the name for the mechanisms our bodies use to keep things, such as our body temperature, stable. So, whether it is 5°C outside or 35°C, our body remains at about 35°C to 37.5°C. When we have a fever and our temperature goes up to 38°C and above, we begin to feel unwell.

When we're in hot conditions, our bodies try to cool down by sweating and dilating blood vessels near the skin to allow heat to radiate out. But if this doesn't work and we can’t cool down, we become ill.

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Babies and toddlers are not only more likely to be affected by this more quickly but, obviously, they also often can’t always tell us what is wrong.

What are the signs of heatstroke?

Heatstroke (sunstroke) happens when the systems in your child’s body to keep them cool stop working and their temperature increases to 40°C and above. It can develop from heat exhaustion. The key signs are that your child may:

  • Feel sick and vomit
  • Have a headache
  • Breathe very quickly and have a rapid pulse (children's and babies' respiratory and pulse rates are naturally faster than adults, but they go up even further in heatstroke)
  • Become irritable, agitated or confused

It's also important to know that, although with heat exhaustion there is lots of sweating, in heatstroke sweating stops.

If untreated, a child with heatstroke can have a seizure, lose consciousness and even die.

What to do if you think your child has heatstroke

Heatstroke is a medical emergency. You need to:
  • Take your child inside and call 999 for an ambulance
  • Stay with your child
  • Take off their clothes 
  • Lie them down and raise their feet slightly
  • Sponge them down with cool, but not ice cold, water and fan them 
  • If they are conscious, encourage them to drink water
  • If they lose consciousness, put them in the recovery position 

How can I prevent my child getting heat exhaustion or heatstroke?

It's always a good idea to be careful about exposing your child to too much direct heat and also to always dress them appropriately for the weather.

Dress your child in loose clothes of natural fibres, if possible, and try to keep them out of the sun between 11am and 3pm when it is at its hottest.
Dr Philippa Kaye

Make sure your baby or child is drinking plenty during hot weather. Treats such as ice lollies and fruit like watermelon can help children to consume more liquid.

But do remember that heat exhaustion can affect a child inside in a hot room, too.

At night, when the temperature inside your home is hotter than outside, open windows to let cool air in (do make sure your windows are child-proofed though).

In the day, when it is cooler inside than outside, then close your windows and blinds or curtains to keep the cool air in.

About our expert Dr Philippa Kaye

Dr Philippa Kaye works as a GP in both NHS and private practice. She attended Downing College, Cambridge, then took medical studies at Guy’s, King’s and St Thomas’s medical schools in London, training in paediatrics, gynaecology, care of the elderly, acute medicine, psychiatry and general practice. Dr Philippa has also written a number of books, including ones on child health, diabetes in childhood and adolescence. She is a mum of 3.

Pics: Getty