Many people associate heatstroke with lying in the sun, but doctors warn that it can happen anywhere the body is unable to get rid of heat — including indoors.
What is heatstroke?
Heatstroke occurs when the body can no longer control its temperature. Normally, sweating cools us down, but in heatstroke the body’s core temperature rises, often above 40°C, and the body’s own cooling system fails. Organs, including the brain, can be damaged. It is a medical emergency.
It can happen indoors
Direct sunlight is not the key factor; the inability to lose heat is. Risky situations include:
- closed, poorly ventilated rooms, especially when humidity is high and sweat cannot evaporate;
- physical effort in warm conditions, such as exercise, sport or heavy work in a hot gym, garage or kitchen.
Other factors
The risk increases when:
- humidity is high, above around 60%;
- there is little or no air movement;
- air pollution is high;
- people live in dense urban areas where buildings and asphalt hold the heat, especially at night.
Who is most at risk?
- older people, particularly those who live alone;
- people with chronic illnesses such as heart failure, diabetes, kidney disease or dementia;
- people taking several medicines, some of which affect the body’s ability to cope with heat;
- babies and young children;
- outdoor workers and people exercising in the heat.
Doctors describe one of the highest-risk profiles as an elderly woman living alone with several health conditions.
Warning signs
- A body temperature of 40°C or more.
- Confusion, agitation or unusual behaviour.
- Hot, red skin, which may be dry or sweating.
- Nausea or vomiting.
- Rapid breathing and heartbeat.
- Headache.
What to do
- Call 112 immediately.
- Move the person somewhere cooler — shade, an air-conditioned room or near a fan.
- Remove excess clothing.
- Cool them quickly: apply cool, wet cloths to the neck, armpits and groin, or use cool (not icy) water.
- Give small sips of water only if the person is fully conscious and able to swallow.
Prevention
- Drink water regularly.
- Keep your home cool: close blinds during the day and ventilate at night.
- Avoid physical effort in the hottest hours.
- Check on older relatives and neighbours during heatwaves.
