Summer brings wonderful days outdoors, but heat can also be dangerous for little ones. Children are much more vulnerable to heat than adults, and infants can neither communicate that they're hot nor move to the shade on their own.

Here's a complete guide to heatstroke and sunstroke in children — from early warning signs to first aid and prevention.

The Difference Between Heatstroke and Sunstroke

Many people use these terms interchangeably, but there is a difference:

Sunstroke (sun poisoning/heat exhaustion of the head) occurs when the head and neck are exposed to direct sunlight over time. It primarily affects the brain and meninges, and can cause headache, nausea, dizziness, and in severe cases, seizures.

Heatstroke is a more serious condition where the entire body overheats. Core temperature rises above 104°F (40°C), and the body can no longer regulate its temperature. Heatstroke can occur without direct sun exposure — for example, in a hot car.

A child left in a car in the sun can develop life-threatening heatstroke in just 15 minutes. The temperature inside a parked car can rise to over 140°F (60°C) even on a day when it's only 68°F (20°C) outside. Never leave children alone in the car.

Why Children Are Especially Vulnerable

Children have several physiological traits that make them more susceptible to heat:

Larger body surface area relative to weight — they absorb more heat from their surroundings
Less efficient sweating — children sweat less than adults and can't cool down as effectively
Higher metabolism — children produce more body heat relative to their size
Immature temperature regulation system — especially in infants
Can't communicate — infants and toddlers can't express that they're hot or thirsty

Infants under 1 year are the most vulnerable. They can't move away from the sun, remove clothing, or ask for a drink.

Signs of Heat Exhaustion and Heatstroke

Heat exhaustion develops gradually. The earlier you spot the signs, the easier it is to treat.

Early Signs (Heat Exhaustion)

The child's face is redder than usual
Sweating heavily (or paradoxically: stops sweating)
Thirstier than usual
Appears limp, tired, or irritable
Skin feels hotter than normal
Breathing faster than usual
Demands more breast or bottle feeds than usual (infants)

Serious Signs (Heatstroke)

Very hot, red, and dry skin (the child has stopped sweating)
Temperature above 104°F (40°C)
Confusion or reduced consciousness
Seizures
Vomiting
Rapid, weak pulse
The child is difficult to wake

Call 911 immediately if the child shows signs of heatstroke: temperature above 104°F (40°C), stopped sweating, seizures, confusion, or reduced consciousness. Heatstroke is a medical emergency.

Signs of Sunstroke

Sunstroke can develop over hours after sun exposure, and symptoms may appear with a delay:

Headache (older children can report this, toddlers cry and are restless)
Nausea and vomiting
Stiff neck
Dizziness
Red, hot skin on the face and head
Fever
In severe cases: seizures, loss of consciousness

In infants: Watch for crying, restlessness, spitting up, lethargy, and refusing breast or bottle. Infants cannot tell you they have a headache.

Parent cooling down a child with water in the shade under a tree in a park

First Aid for Heatstroke and Sunstroke

First Aid for Heatstroke (Call 911 First)

Move the child to a cool place — indoors with air conditioning or into the shade
Remove excess clothing — let the child lie in just a diaper or underwear
Cool actively — place cool, damp towels on the forehead, neck, armpits, and groin
Don't lower the temperature too quickly — avoid ice baths, as they can cause shock
Do NOT give fluids if the child is unconscious or confused
Place the child in the recovery position if they are vomiting
Wait for the ambulance — heatstroke requires professional treatment

First Aid for Sunstroke

Move the child to shade or indoors
Cool the head with damp, lukewarm cloths
Give fluids in small sips if the child is awake and alert
Let the child rest with the head slightly elevated
Contact a doctor if the child is under 1 year, vomits repeatedly, or doesn't improve after 30 minutes

Rule of thumb for cooling: Use lukewarm, not ice-cold water. Ice-cold water causes blood vessels in the skin to constrict, which actually makes it harder for the body to release heat.

Prevention: How to Protect Your Child

Clothing and Protection

Light, loose-fitting, and breathable clothing in natural materials (cotton, linen)
Sun hat with a wide brim that covers the face, ears, and neck
Sunscreen with at least SPF 30 on all exposed skin areas (from 6 months of age)
For infants under 6 months: avoid direct sun entirely. Use shade and clothing

Hydration

Offer drinks regularly — don't wait until the child asks
Breastfed infants: Offer the breast more frequently in the heat. Breast milk provides both hydration and nutrition
Children over 6 months: Water is best. Avoid sugary drinks
Always bring a water bottle on outings, in the car, and at the beach

Timing and Activity

Avoid direct sun between 10 AM and 3 PM — when UV radiation is strongest
Limit intense activity in strong heat — play in the shade instead
Take frequent breaks in the shade during outdoor activities
Never let children sleep in direct sunlight — not even under a parasol that may shift

Sleep Conditions

Don't overdress the baby at night during hot periods
Use a thin sleep sack or just a bodysuit
Ventilate the bedroom
Check that the room temperature doesn't exceed 68–72°F (20–22°C)

Check your child's temperature: Feel the child's chest or back of the neck — not the hands or feet. If the chest is warm and sweaty, the child has too many layers on. Use the same number of layers as yourself, plus one thin layer for infants.

In the Car

Never leave children alone in the car — not even for a minute
Use sun shades on rear windows
Check that the car seat isn't too hot before placing the child in it
Run the air conditioning for a few minutes before getting in the car
Always have water available on car trips

Heatstroke vs. Febrile Seizures

Some parents confuse heatstroke with febrile seizures. Here's the difference:

	Heatstroke	Febrile Seizures
Cause	External heat (sun, hot car)	Infection with fever
Sweating	Stopped	May sweat
Treatment	Emergency cooling + call 911	Recovery position, wait it out
Occurrence	Relatively rare	3–5% of all children

Frequently Asked Questions

Can a baby get sunstroke in a stroller?

Yes. Many people think the canopy provides protection, but it can create a greenhouse effect that makes it even hotter inside the stroller. Never cover the stroller with a blanket or cloth — it blocks air circulation. Use a breathable sun shade designed for strollers, and avoid direct sunlight.

How hot is too hot for a baby?

Infants should not be exposed to temperatures above 77–80°F (25–27°C) without access to cooling and shade. Indoors, the room temperature should ideally be between 64–72°F (18–22°C). Feel the child's chest — it should be warm but not sweaty.

Does fanning help?

Yes, moving air helps with evaporation and cooling. A fan or fanning with something is a good measure. However, if the air temperature is above 95°F (35°C), a fan can actually make things worse by blowing hot air toward the child.

Can children get heatstroke indoors?

Yes. Heatstroke can occur indoors if the room is very hot and poorly ventilated. Infants who are overdressed in a warm room are especially at risk. Ensure good ventilation and appropriate clothing.

When can I take my baby out in the sun again after sunstroke?

Wait at least 2–3 days after the child is completely symptom-free. The body needs time to recover. Start cautiously with short periods in the shade, and avoid direct sun for the first few days.

Heatstroke and Sunstroke in Children: Symptoms and First Aid