When it happens · 4 min read
Too hot: heat illness and sunburn
A long afternoon outside, a hot car journey, a football session in August. Children become ill from heat much faster than adults do, and the early signs get read as tiredness or a bad mood.
High temperatures can make a child sick very quickly — dehydration, heat cramps, heat exhaustion and heat stroke sit on the same line, and the point of knowing the difference is that the last one is an emergency.
Last updated August 17, 2026
Heat exhaustion, and what to do
Pale, clammy skin with heavy sweating. Headache, nausea, dizziness, muscle cramps, weakness, and a child who has gone quiet and floppy when they were running around twenty minutes ago.
Get them out of the heat immediately — indoors with air conditioning, or deep shade. Take off extra clothing. Cool the skin actively with cool water, wet cloths or a cool bath, and move air across them with a fan.
Give cool drinks in small, frequent amounts if they are alert enough to drink safely. Water is fine for short exposures; for prolonged activity in heat, something with salts in it is better than plain water alone.
They should start to improve fairly quickly. If they do not, or they get worse, treat it as the next thing on the list.
Heat stroke is a 911 call
Skin that is hot and dry, or that has stopped sweating despite the heat. A temperature that keeps climbing. Confusion, agitation, slurred speech, behaving strangely, seizures, or not responding properly.
Call emergency services first, then cool them aggressively while you wait — cool water over the skin, wet cloths, fanning, ice packs at the neck, armpits and groin, a cool bath if you can do it safely. Do not wait for permission to start cooling; the time to a lower core temperature is what determines the outcome.
Do not give fluids to a child who is confused, drowsy or not fully alert.
The car
Never leave a child in a parked car, for any length of time, with any amount of window cracked. The interior heats far faster and far higher than people expect, and children's bodies heat several times faster than adults'.
This kills children every summer at outside temperatures that feel entirely unremarkable, and almost never because someone decided to take a risk — overwhelmingly it is a change in routine and a genuinely forgotten child in a rear-facing seat.
So treat it as a systems problem rather than a character one: something you need in the back seat, a check every single time you lock the car, and a standing arrangement with nursery that they call if a child does not arrive.
Sunburn, and staying ahead of it
Covering up beats sunscreen: lightweight long sleeves and trousers, SPF-rated clothing, a wide-brimmed hat, and shade in the middle of the day. Sunscreen is the last line rather than the first.
For sunburn that has already happened: cool baths or cool compresses, extra fluids, moisturiser, and age-appropriate pain relief. Do not break blisters.
Get it seen if there is blistering over a large area, if there is fever, chills, headache or vomiting with it, or if the child is very young. Sunburn is a burn, and a bad one is treated like one.
Regular water and snack breaks are the cheapest intervention available on a hot day, and children reliably will not take them unless an adult calls them.
Common questions
- How much should they be drinking on a hot day?
- More than they ask for, and on a schedule rather than on demand — children under-drink when they are absorbed in playing. Regular enforced breaks with a drink work better than leaving a bottle nearby.
- They've stopped sweating. Is that good?
- No — it is one of the warning signs. Hot, dry skin in a child who was sweating is a reason to call emergency services and start cooling immediately.
- Is sunscreen enough on its own?
- No. Covering up is the first and best defense, with shade and timing next. Sunscreen matters for the skin you cannot cover, and it is routinely applied too thinly and too rarely to do what the bottle claims.
If it's this, not that
Still not sure
This page is the general answer. Yours is a specific child.
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Where this comes from
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Written from the sources named above, and it is not a substitute for your own doctor. If something feels wrong to you, that instinct is a good enough reason to call — you know yourself and this family better than any page does.