The top warning signs of potentially fatal heat stroke, which can make your heart swell

Mercury reached a sweltering 32.4C at Heathrow in west London on Friday – but while sun-seeking Brits welcome the arrival of hotter weather each year, rising mercury levels also increase the risk of heatstroke and the deadly heatstroke

Last week marked the hottest day of the year so far as Brits sizzled in scorching temperatures.

The mercury reached a sweltering 32.4C at Heathrow in west London on Friday.

Scorching weather made parts of the UK hotter than the Sahara, with temperatures struggling to climb above 23C in Dakhla in Western Sahara.

And after two years of lockdown summer, mild temperatures have been welcomed by millions across the country.

But while sun-seeking Brits welcome the arrival of hotter weather each year, as mercury levels rise, so does the risk of heatstroke, and the deadly heatstroke.

Here, Natasha Holt takes a closer look at the signs and dangers of the potentially deadly condition.

You can get heat stroke when it’s not that hot

Heat exhaustion is caused by prolonged exposure to heat, which triggers symptoms such as headaches, dizziness, and nausea. Left untreated, this can quickly progress to heat stroke, where your core temperature reaches 40°C or more, which can be fatal.

For this reason we tend to think of heat stroke as something that happens abroad in the blazing sun, but in fact it can happen right here in the UK with temperatures in the mid 20’s.

“Heat stroke is associated with hot weather, but it doesn’t have to be record-breaking temperatures,” says Dr. Naveen Puri, Associate Clinical Director at Bupa Health Clinics.

“Sudden exposure to hot weather that you are not used to, for example during a sudden heat wave or after traveling to a hot country, can make you more vulnerable.

“Exercising or playing sports in hot weather also increases risk, even if temperatures don’t skyrocket. Remember that heat stroke should always be treated as a medical emergency.”

Just because you’re not sweating doesn’t mean you’re not at risk

In fact, the opposite is often the case. “When you have heat stroke, your skin tends to feel hot and dry rather than sweaty,” warns Dr. puri “This is a danger sign as it means you are very dehydrated.

“If you’ve exercised in a hot climate you’re probably going to sweat a lot, but when you have heat stroke your skin can just feel clammy or even dry. This is a sign to see a doctor urgently.”

You will feel cold rather than hot

Instead of feeling boiling hot, you may feel cold and clammy after heat stroke sets in, even when the temperature is high.

“If your body is having trouble regulating your temperature, you may feel cold or suddenly have chills,” he says
Dr Puri.

“This is a warning sign of heat stroke and you should take steps to cool down quickly.”

Headaches can be the first sign

“Headaches can be an early sign of heat exhaustion, which means you need to try to cool down,” says Dr. puri

“If you can’t lower your body temperature within 30 minutes and develop a throbbing, pounding headache, it may be a sign of heat stroke, which is more serious and may require medical attention.”

It can cause you to behave strangely

If you or someone you are with starts acting out of character in the sun, alarm bells should be ringing because heat stroke can affect your behavior.

“Some people with heat stroke may become confused, agitated, or irritable, or even slur their speech,” says Dr. puri “In severe cases, they can have a seizure or lose consciousness, so it’s really important to act quickly if you notice this in yourself or a loved one.”

It can damage your vital organs

Not many people know that heatstroke, even if treated, can cause permanent damage to your body.

“Heat stroke can cause your vital organs, such as your heart, kidneys or liver, to swell, and sometimes this can be permanent,” says Dr. puri

Some medications can help

“Certain medications can affect your ability to effectively regulate body temperature or stay hydrated, making you more prone to heat stroke,” says Dr. puri

“People taking beta-blockers, diuretics, antidepressants, or vasoconstrictors should be extra cautious when it’s hot,” he adds.

You don’t have to be outside

Vets warn against leaving dogs in hot cars, and the same goes for humans. “You don’t have to be outside in direct sun to get heat stroke,” says Dr. puri “Cars can get very hot very quickly, so don’t leave anyone, especially young children, in the car during warmer weather.”

Pregnancy makes you more vulnerable

“When you’re pregnant, your body has to work harder to cool you down and keep you hydrated,” says Dr. puri

“Both of these factors can increase your risk of heat exhaustion or heat stroke, so stay out of direct sun in hot weather and increase your fluid intake.”

Obesity is a risk

Carrying excess weight is associated with poor heat tolerance.

“Being overweight, obese, or not getting enough exercise can put you at a higher risk of heat stroke,” says Dr. puri “If this is you, wear light clothing and avoid being outside during the hottest part of the day. Cool off regularly with cold drinks and lukewarm baths.”