How long does heatstroke last? Symptoms of sunstroke, how long it takes to recover, and possible complications

The summer of 2023 is shaping up to be a scorcher for much of the UK as temperatures continue to soar.

People in the UK have seen temperatures hitting above 30 degrees Celsius in early June, with warnings that the searing heat is set to become a common fixture of the normally-drab British summer as a result of climate change.

British residents may find themselve out and about and enjoying the sunshine but there are warnings of an increased risk of sunstroke. Hot weather and exercise are both causes of heatstroke - or sunstroke - according to the NHS.

Here’s everything you need to know about heat exhaustion and heatstroke, including signs, symptoms and how to prevent it.

How can I check for signs of heat exhaustion?

Heat exhaustion is not usually serious, but it can sometimes turn into heatstroke.

The NHS notes that signs of heat exhaustion include:

• a headache
• dizziness and confusion
• loss of appetite and feeling sick
• excessive sweating and pale, clammy skin
• cramps in the arms, legs and stomach
• fast breathing or pulse
• temperature of 38C or above
• being very thirsty

How can I cool someone down?

If someone has heat exhaustion, follow these 4 steps:

1. Move them to a cool place.
2. Get them to lie down and raise their feet slightly.
3. Get them to drink plenty of water. Sports or rehydration drinks are ok.
4. Cool their skin. Spray or sponge them with cool water and fan them. Cold packs around the armpits or neck are good.

Stay with them until they’re better. They should start to cool down and feel better within 30 minutes.

The symptoms are often the same in adults and children, but children may become floppy and sleepy.

If someone is showing signs of heat exhaustion, they need to be cooled down.

What are the signs of heatstroke?

You should call 999 if you or someone else have any signs of heatstroke, which include:

• feeling unwell after 30 minutes of resting in a cool place and drinking plenty of water
• not sweating even though too hot
• a temperature of 40C or above
• fast breathing or shortness of breath
• feeling confused
• a fit (seizure)
• loss of consciousness
• not responsive

The NHS says: “Heatstroke can be very serious if not treated quickly.

“Put the person in the recovery position if they lose consciousness while you’re waiting for help.”

How long does sunstroke last?

The NHS website notes, “Heat exhaustion is not usually serious if you can cool down within 30 minutes. If it turns into heatstroke, it needs to be treated as an emergency."

Harvard Health Publishing explains, “It is standard for a person with heat stroke to stay in the hospital for one or more days so that any complications can be identified quickly.

Complete recovery from heat stroke and its effects on body organs may take two months to a year.”

How can I prevent heat exhaustion and heatstroke?

The NHS explains that there’s a high risk of heat exhaustion or heatstroke during hot weather or exercise.

To help prevent heat exhaustion or heatstroke, you should:

• drink plenty of cold drinks, especially when exercising
• take cool baths or showers
• wear light-coloured, loose clothing
• sprinkle water over skin or clothes
• avoid the sun between 11am and 3pm
• avoid excess alcohol
• avoid extreme exercise

This will also prevent dehydration and help your body keep itself cool.

The NHS adds, “Keep an eye on children, the elderly and people with long-term health conditions (like diabetes or heart problems) because they’re more at risk of heat exhaustion or heat stroke.”

Are there any possible complications?

Children, older people and people with long-term health conditions (such as diabetes or heart problems) are more at risk of heat exhaustion or heatstroke.

Who is more vulnerable to hot weather?

The most vulnerable people during a heatwave are:

• older people – especially those over 75 and female
• those who live on their own or in a care home
• people who have a serious or long-term illness including heart or lung conditions, diabetes, kidney disease, Parkinson’s disease or some mental health conditions
• people who are on multiple medicines that may make them more likely to be badly affected by hot weather
• those who may find it hard to keep cool – babies and the very young, the bed bound, those with drug or alcohol addictions or with Alzheimer’s disease
• people who spend a lot of time outside or in hot places – those who live in a top-floor flat, the homeless or those whose jobs are outside