This NHS content is written for people in England. Services, entitlements and contact routes may differ in other countries.
Symptoms of heat exhaustion and heatstroke
Symptoms of heat exhaustion
The symptoms of heat exhaustion include:
- tiredness
- dizziness
- headache
- feeling sick (nausea) or being sick (vomiting)
- excessive sweating and skin becoming pale and clammy (a change in skin colour can be harder to see on brown or black skin)
- cramps in the arms, legs and stomach
- a high temperature
- being very thirsty
- feeling irritable
The symptoms of heat exhaustion are often the same in adults and children.
If someone is showing signs of heat exhaustion they need to be cooled down and given fluids.
Symptoms of heatstroke
The symptoms of heatstroke include:
- a very high temperature
- hot skin without sweating
- fast breathing and a fast heartbeat
- confusion and restlessness
- seizure (fit)
- loss of consciousness
Heatstroke is a medical emergency. Get immediate medical help if someone has the symptoms of heatstroke.
Things you can do to cool someone down
If someone has heat exhaustion, follow these 4 steps:
- Move them to a cool place.
- Remove all unnecessary clothing like a jacket or socks.
- Give them plenty of water to drink – you can also give them an isotonic sports drink or oral rehydration powder that you mix with water, which will help replace salt lost through sweating.
- Cool their skin – spray or sponge them with cool water and fan them. Cold packs, wrapped in a cloth and put under the armpits or on the neck are good too.
Stay with them until they're better.
They should start to cool down and feel better within 30 minutes.
Get help from NHS 111 now if:
- you or someone else have symptoms of heat exhaustion that you're struggling to treat or you need advice about
You can call 111 or get help from 111 online .
Call 999 now if:
You or someone else have signs of heatstroke, including:
- still being unwell after 30 minutes of resting in a cool place, being cooled and drinking fluids
- a very high temperature
- hot skin that's not sweating and might look red (this can be harder to see on brown or black skin)
- a fast heartbeat
- fast breathing or shortness of breath
- confusion and lack of coordination
- a seizure or fit
- loss of consciousness
A&E safety messaging (for 999 only)
Do not drive yourself to A&E.
The person you speak to at 999 will give you advice about what to do.
What to do while waiting for help with heatstroke
Wrap the person in a cool, wet sheet, or fan them or sponge them down with cold water while you wait for help to arrive.
If they lose consciousness while you're waiting for help, put them in the recovery position and tell the ambulance service. Check their breathing and pulse and carry out CPR if they show no sign of life.
Preventing heat exhaustion and heatstroke
There's a high risk of heat exhaustion or heatstroke during hot weather or exercise.
To help prevent heat exhaustion or heatstroke:
- drink more cold drinks, especially if you're active or exercising
- wear light-coloured, loose clothing
- avoid the sun between 11am and 3pm
- avoid drinking too much alcohol
- avoid extreme exercise
- if you're inside on a very hot day, close curtains, and close windows if it's hotter outside than in your home, and turn off electrical equipment and lights that get hot
This will also prevent dehydration and help your body keep itself cool.
Check on children, older people and people with long-term health conditions, such as diabetes or heart problems, as they're more at risk of heat exhaustion or heatstroke.
Heat exhaustion and heatstroke
Heat exhaustion and heatstroke
Heat exhaustion and heatstroke
Symptoms of heat exhaustion include headache and feeling sick. Symptoms of heatstroke include a very high temperature and hot skin without sweating.
The main way to treat heat exhaustion is to cool down by moving to a cool place and drinking fluids. Heatstroke needs to be treated in hospital.
To avoid heat exhaustion and heatstroke during hot weather or exercise, drink lots of cold drinks and wear light-coloured, loose clothing.
Content supplied by the NHS website, refreshed 19 August 2026. View the original NHS article ↗
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