What medical conditions get worse in heat?
Heatwave: how to cope in hot weather
Most of us welcome hot weather, but when it’s too hot, there are health risks. During heatwaves, more people than usual get seriously ill or die. If hot weather hits this summer, make sure it does not harm you or anyone you know.
Why is a heatwave a problem?
The main risks posed by a heatwave are:
- not drinking enough water (dehydration)
- overheating, which can make symptoms worse for people who already have problems with their heart or breathing
- heat exhaustion and heatstroke
Who’s most at risk?
A heatwave can affect anyone, but the most vulnerable people 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
Tips for coping in hot weather
Keep out of the heat if you can. If you have to go outside, stay in the shade especially between 11am and 3pm, wear sunscreen, a hat and light clothes, and avoid exercise or activity that makes you hotter.
Cool yourself down. Have cold food and drinks, avoid alcohol, caffeine and hot drinks, and have a cool shower or put cool water on your skin or clothes.
Keep your living space cool. Close windows during the day and open them at night when the temperature outside has gone down. Electric fans can help if the temperature is below 35 degrees. Check the temperature of rooms, especially where people at higher risk live and sleep.
You can also get help from the environmental health office at your local council, if you think a hot house is affecting your health or someone else’s. They can inspect a rented home for hazards to health, including excess heat.
Watch out for signs of heat-related illness
If you or someone else feels unwell with a high temperature during hot weather, it may be heat exhaustion or heatstroke.
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Next review due: 10 August 2025
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Hot weather advice
Hot weather can cause heat exhaustion in people and animals. Also, bacteria on food and rubbish develop more quickly in the heat. Find out how to stay safe around the home in hot weather, including keeping cool and taking extra care with food and waste.
Looking after your health in hot weather
Summer temperatures in Northern Ireland can be a risk to health.
It is important to make sure you and those you care for are suitably hydrated.
In a heatwave, you may get dehydrated and your body may overheat. This can lead to heat exhaustion or heatstroke , which both need urgent treatment. Heatstroke can cause serious damage to your body or even death.
Heat exhaustion and heatstroke
Symptoms of heat exhaustion include:
- nausea and vomiting
- muscle weakness or cramps
- pale skin
- high temperature
If you think you have heat exhaustion, you should move somewhere cool and drink plenty of water. If you can, take a lukewarm shower or sponge yourself down with cold water.
If heat exhaustion is untreated, you could develop heatstroke. Heatstroke can also occur suddenly and without any warning.
Symptoms of heatstroke include:
- intense thirst
- hot, red and dry skin
- a sudden rise in temperature
- loss of consciousness
If you have these symptoms during a heatwave, rest for a few hours, keep cool and drink water. If the symptoms don’t go away or get worse, seek medical advice.
Heatstroke can kill. It can develop very suddenly and may lead very quickly to unconsciousness.
If you suspect someone has heatstroke, call 999 immediately.
While waiting for the ambulance:
- move the person somewhere cooler if possible
- increase ventilation by opening windows or using a fan
- cool them down as quickly as possible by loosening their clothes, sprinkling them with cold water or wrapping them in a damp sheet
- if they are conscious, give them water to drink
- don’t give them aspirin or paracetamol
People at risk during hot weather
Heat can affect anyone, but some people are at greater risk of serious harm from the effects of extreme heat. These include:
- older people, especially those over 75 years of age
- babies and young children
- people with mental health problems
- people on certain types of medication – ask your doctor if you are at risk
- people with a chronic health condition such as breathing or heart problems
- people who already have a high temperature from an infection
- people who misuse alcohol or use illegal drugs
- people with mobility problems
- people who are physically active such as manual workers or sportspeople
If anyone you know is likely to be at risk during a heatwave, help them to get the advice and support they need.
Older people living on their own should be visited daily to check they are well.
What to do in hot weather
You can take steps to protect yourself and others from the effects of very hot weather.
Check the weather forecast so you know if a heatwave is on the way and plan ahead to reduce the risk of ill-health from the heat.
Keep out of the heat
- plan your day so that you can stay out of the heat when possible
- try to stay out of the sun, particularly when it is at its highest between 11.00 am and 3.00 pm
- do strenuous outdoor activities, like sports, DIY or gardening during cooler parts of the day
- stock up on supplies like medicines, food and non-alcoholic drinks, so you won’t have to go out in the heat
- if you must go out, stay in the shade and wear a hat and loose-fitting cotton clothes
- use a sun cream with a high sun protection factor — also known as ‘SPF’ — for protection from the sun’s harmful ultraviolet (UV) radiation — SPF 15 or greater is advised with a UVA Rating of at least 4 stars
- don’t leave babies or children in a parked car
For more information go to:
- Protection from the sun
Keep you and your house cool
In hot weather, stay inside the coolest rooms in your house as much as possible. These are probably the rooms that get little sun during the day. To help keep all rooms in your house cool, you can:
- close pale-coloured curtains
- take care with metal blinds and dark curtains as they absorb heat — consider replacing them or putting reflective material in between them and the window
- keep windows closed when it’s hotter outside than inside, but open them if the room gets too hot
- open windows at night when the air is cooler, but close ground floor windows when you leave the house or go to bed
- place a thermometer in your main living room and bedroom to keep a check on the temperature
- turn off non-essential lights and electrical equipment — they generate heat
- keep indoor plants and bowls of water in the house as evaporation helps keep cool the air
- take cool showers or baths and splash yourself several times a day with cold water, especially your face and the back of your neck
- drink regularly even if you do not feel thirsty – water or fruit juice are best
- try to avoid alcohol, tea and coffee as these can cause dehydration
- avoid heavy and hot food; fruit and salads can help keep you hydrated
Take extra care with food in hot weather
When it’s hot, bacteria on food can multiply very quickly, which increases the risk of food poisoning.
Find more advice on keeping food safe in the hot weather at:
Take care with bins and waste
Bins and waste can attract flies and start to smell in the heat, so make sure you:
- recycle as much as possible to reduce waste
- move bins out of direct sunlight and keep their lids closed at all times to prevent access by flies or rodents
- use bio-degradable bags recommended by your council for food waste and squeeze the air out of the top of the bags before you tie them then place them in your food waste or garden waste bin
- bag nappies before placing in your waste bin
- wash and/ or disinfect waste containers regularly, both inside and out but remember to rinse off any cleaning chemicals afterwards to prevent yourself or council workers being splashed by the chemicals
For more information about bin and waste collection and recycling, contact your local council.
- Bins and waste collection
Looking after pets
You must also take care of pets and other animals during warm weather. Make sure they have plenty of ventilation and liquid to stay hydrated.
Never leave animals inside a car on a hot day and make sure they have:
- plenty of clean, fresh water to drink
- a cool and shady place to rest
It’s also important to cover pet food dishes to prevent flies laying eggs on the food.
Contact a vet if you are worried that an animal is suffering from heatstroke.
More information about looking after pets in hot weather is on the Royal Society for the Prevention of Cruelty to Animals (RSPCA) website.
- Seasonal advice for summer
- Dogs in cars
During hot and dry weather, avoid bonfires and be extra careful with barbecues. Dry ground in the summer increases the risk of fire.
- Fire safety and prevention
More useful links
- Protection from the sun
- GP out of hours service
- Support and safety in your home
- Illnesses and conditions
Heat Cramps, Exhaustion, and Stroke
Heat-related illnesses happen when a person is exposed to abnormal or prolonged amounts of heat and humidity without relief or adequate fluids. Children and adolescents adjust more slowly than adults do to changes in environmental heat and are thus more vulnerable to heat-related illnesses.
There are three types of heat-related illnesses:
- Heat cramps are the mildest form of heat injury and consist of painful muscle cramps and spasms that occur during or after intense exercise and sweating in high heat.
- Heat exhaustion is more severe than heat cramps and results from a loss of water and salt in the body. It occurs in conditions of extreme heat and excessive sweating without adequate fluid and salt replacement. Heat exhaustion occurs when the body is unable to cool itself properly and, if left untreated, can progress to heat stroke.
- Heat stroke, the most severe form of heat illness, occurs when the body’s heat-regulating system is overwhelmed by excessive heat. It’s a life-threatening emergency and requires immediate medical attention.
Why your child might be vulnerable
Children produce more heat with activity than adults, and they sweat less. Sweating is one of the body’s normal cooling mechanisms; so children can become overheated when playing or exercising. Children and adolescents often do not think to rest when having fun and may not drink enough fluids when playing, exercising, or participating in sports.
Which children are especially vulnerable to heat-related illnesses?
Children and adolescents with chronic health problems, or those who take certain medicines, may be more susceptible to heat-related illnesses. Children and adolescents who are overweight or wear heavy clothing during exertion, such as marching band or football uniforms, are also more susceptible.
What are symptoms and first-aid measures for heat-related illnesses?
The following chart contains the most common symptoms of heat-related injuries. However, each adolescent may experience symptoms differently. In addition specific treatment will be determined by your adolescent’s physician and may include some, or more, of the following:
painful cramps, especially in the legs
flushed, moist skin
mild fever, usually less than 102.5 F
Move to a cool place and rest.
Remove excess clothing and place cool cloths on skin; fan skin
Give cool sports drinks containing salt and sugar such as Gatorade
Stretch cramped muscles slowly and gently
pale, moist skin
usually has a fever over 102 degrees
anxiety, and faint feeling
Move to a cool place and rest
Give cool sports drinks containing salt and sugar such as Gatorade
If no improvement or unable to take fluids, call your adolescent’s physician or take your child to an emergency department immediately. IV (intravenous) fluids may be needed.
high fever, usually over 104 degrees
rapid heart rate
loss of appetite
seizures, coma, and death are possible
Move to a cool place and rest.
Call 911 or your local emergency medical service. Heat stroke is a life-threatening medical emergency and needs to be treated by a physician
Remove excess clothing and drench skin with cool water; fan skin.
Place ice bags on the armpits and groin areas.
Offer cool fluids if alert and able to drink.
Can heat-related illnesses be prevented?
Some general guidelines to help protect your adolescent from heat-related illnesses include:
- Encourage your adolescent to drink plenty of fluids during vigorous or outdoor activities (including sunbathing), especially on hot days. Good choices include water and sports drinks; avoid alcohol and fluids with caffeine such as tea, coffee, and cola, as these can lead to dehydration.
- Make sure your adolescent dresses in light colored, lightweight, tightly-woven, loose-fitting clothing on hot days.
- Have your adolescent schedule vigorous activity and sports for cooler times of the day. Encourage him or her to take rest periods in shady or cool areas.
- Makes sure your adolescent is protected from the sun (SPF 15) and wears a hat and sunglasses, and uses an umbrella.
- Encourage your adolescent to increase time spent outdoors gradually so his or her body gets used to the heat.
- Teach adolescents to take frequent drink breaks and «wet down» or mist themselves with a spray bottle to avoid becoming overheated.
- Encourage your adolescent to spend as much time indoors as possible on very hot and humid days.
- Teach your adolescent to warm-up and cool-down before and after exercising.
- If your adolescent has a medical condition or is taking medication, consult your adolescent’s physician for further advice for preventing heat-related illnesses.