Hot weather can be enjoyable, whether you’re making the most of the latest UK heatwave or heading abroad for a summer holiday. However, prolonged exposure to high temperatures can put your health at risk.
Every summer, healthcare services see people affected by heat-related illnesses, many of which are preventable. Two of the most common conditions are heat exhaustion and heatstroke.
Although they are related, they are not the same. Heat exhaustion is usually mild if treated quickly, while heatstroke is a medical emergency that requires immediate attention.
Knowing how to recognise the warning signs could help you protect yourself, your family, or someone else who becomes unwell in the heat.
What causes heat-related illness?
Your body is designed to regulate its temperature, mainly through sweating. However, if you’re exposed to high temperatures for prolonged periods, especially if you’re physically active or not drinking enough fluids, your body may struggle to cool itself effectively.
Young children, older adults, pregnant women and people with long-term health conditions are generally more vulnerable, but anyone can be affected.
What is heat exhaustion?
Heat exhaustion occurs when your body loses too much water and salt through sweating. It isn’t usually serious if recognised early, but it can develop into heatstroke if left untreated.
Common symptoms include:
- Heavy sweating
- Feeling tired or weak
- Headache
- Dizziness or light-headedness
- Muscle cramps
- Nausea or vomiting
- Fast pulse
- Cool, pale or clammy skin
- Intense thirst
Many people describe feeling faint or unusually exhausted, even after relatively light activity.
How to treat heat exhaustion
If someone has symptoms of heat exhaustion, it’s important to cool them down as quickly as possible.
You should:
- Move them to a cool or shaded place
- Encourage them to lie down with their legs slightly raised if they feel faint
- Offer cool water or an oral rehydration solution in small sips
- Loosen or remove unnecessary clothing
- Cool their skin with damp cloths, cool water or a fan if available
Most people begin to recover within around 30 minutes. If symptoms do not improve, become worse, or the person is unable to drink fluids, seek medical advice promptly.
What is heatstroke?
Heatstroke is much more serious. It develops when the body’s temperature rises to dangerous levels and it can no longer cool itself effectively. Without rapid treatment, heatstroke can damage vital organs and may become life-threatening.
Unlike heat exhaustion, heatstroke requires immediate emergency medical attention.
Warning signs include:
- Confusion or unusual behaviour
- Slurred speech
- Loss of consciousness
- Seizures
- A very high body temperature
- Hot, flushed skin (which may be dry or still sweating)
- Rapid breathing
- Fast heartbeat
Someone with heatstroke may seem disorientated, struggle to respond normally, or collapse unexpectedly.
What should you do if you suspect heatstroke?
Call emergency services immediately.
While waiting for help:
- Move the person somewhere cool.
- Remove excess clothing.
- Cool them rapidly using cool water, wet towels or ice packs wrapped in cloth placed around the neck, armpits and groin.
- Fan them continuously if possible.
Do not delay seeking emergency medical help while trying to cool them down yourself.
Staying safe during hot weather
Whether you’re enjoying the sunshine at home or abroad, a few simple precautions can make a big difference.
Stay hydrated
Drink fluids regularly throughout the day, even if you don’t feel thirsty. Water is usually the best option. If you’re sweating heavily for long periods, drinks that replace electrolytes may also be helpful.
Avoid the hottest part of the day
If possible, limit strenuous activity between around 11am and 3pm, when temperatures and UV levels are often at their highest.
Dress appropriately
Wear:
- Lightweight, loose-fitting clothing
- Light-coloured fabrics
- A wide-brimmed hat
- Sunglasses with UV protection
These simple measures can help your body stay cooler.
Protect yourself from the sun
Apply sunscreen with at least SPF 30 and reapply regularly, particularly after swimming or sweating. Remember that preventing sunburn also reduces additional stress on your body during hot weather.
Plan ahead when travelling
Many popular holiday destinations now experience prolonged periods of extreme heat during the summer months.
If you’re travelling abroad:
- Carry water with you during excursions
- Take regular breaks in the shade
- Plan sightseeing for cooler parts of the day
- Make sure children and older relatives stay well hydrated
- Know where to seek medical help if needed
A consultation at your local travel health clinic before you leave can provide advice tailored to your destination, particularly if you’re travelling with young children, older adults or someone with a medical condition.
Heat exhaustion and heatstroke are both caused by exposure to high temperatures. With much of Europe experiencing increasingly hot summers and the UK seeing more frequent and prolonged heatwaves, understanding the warning signs has never been more important.