Heat exhaustion and heatstroke
Heat exhaustion and heatstroke are two potentially serious conditions that can occur if you get too hot.
They usually happen during a heatwave or in a hot climate but can also occur when you’re doing very strenuous physical exercise.
Heat exhaustion is where you become very hot and start to lose water or salt from your body, which leads to the symptoms listed below and generally feeling unwell.
Heatstroke is where the body is no longer able to cool itself and a person’s body temperature becomes dangerously high (sunstroke is when this is caused by prolonged exposure to direct sunlight).
Heatstroke is less common, but more serious. It can put a strain on the brain, heart, lungs, liver and kidneys, and can be life-threatening.
If heat exhaustion isn’t spotted and treated early on, there’s a risk it could lead to heatstroke.
Signs and symptoms
Heat exhaustion or heatstroke can develop quickly over a few minutes, or gradually over several hours or days.
Signs of heat exhaustion can include tiredness and weakness, feeling faint or dizzy, a decrease in blood pressure, a headache, muscle cramps, feeling and being sick, heavy sweating, intense thirst, a fast pulse and /or urinating less often and having much darker urine than usual. If left untreated, more severe symptoms of heatstroke can develop, including confusion, disorientation, seizures (fits) and a loss of consciousness.
What to do
If you notice that someone has signs of heat exhaustion, you should get them to lie down in a cool place (such as a room with air conditioning or somewhere in the shade), remove any unnecessary clothing to expose as much of their skin as possible, cool their skin –use whatever you have available, such as a cool, wet sponge or flannel, cold packs around the neck and armpits, or wrap them in a cool, wet sheet and fan their skin while it’s moist. This will help the water to evaporate, which will help their skin cool down. Get them to drink fluids – this should ideally be water, fruit juice or a rehydration drink, such as a sports drink. Stay with the person until they’re feeling better. Most people should start to recover within 30 minutes.