Rapid heartbeat? Muscle cramps? Vomiting? Coma? These are just a few of the things that can happen to you if you get sunstroke.

It's not often the Department of Health has to hand out advice on how to avoid this particular ailment - it's more used to dealing with flu epidemics - but, for the hottest day of the year so far, here are a few tips on how to stay healthy in the sweltering heat...

Stay in the shade or indoors The sun is at its most dangerous between 11am and 3pm. Find shade under umbrellas, trees or canopies. It is worth remembering that the temperature is at least a couple of degrees cooler if you are by water. Use sunscreen and cover up If you can't avoid being out in the sun apply sunscreen (factor 15+) and wear a t-shirt, hat and sunglasses. Increase your fluid intake The normal recommended daily intake of fluid is 2.5 litres or 8 glasses per day. In extreme heat experts recommend you drink more and include a range of different fluids. Ventilate your home Keep windows open all day and all night and use fans. This is particularly important at night, when the body cools down. Look after the elderly Older people are more prone to the effects of heat. If you have older relatives or neighbours you can help simply by checking on them and reminding them to drink plenty and often. They should have a mixture of drinks including tea, fruit juice and water. Also help them to keep their house as cool as possible, using a fan if necessary. Protect children Keep a close eye on young children, who need plenty of fluids. A good way to check if they are drinking enough is that they are passing urine regularly and that it is not too dark. You should check nappies regularly. Babies and the very young must be kept out of the sun. Avoid excessive physical exertion If you are taking physical exercise you need to drink half a litre of fluid at least half an hour beforehand and continue to replenish your fluids after exercising. Know the perils of outdoor eating Warm summer weather is a perfect breeding ground for bacteria so it is especially important to keep hot foods hot and cold foods cold until you are ready to eat them. When barbecuing always make sure you cook meat until it is piping hot, none of it is pink and all juices run clear. Be sensible with alcohol Hot weather speeds up the effects of alcohol so extra care should be taken when drinking. Alcohol will lead to dehydration so make sure that you alternate alcoholic drinks with water or fruit juice. Keep cool at work The office is often the coolest place to be in a heatwave. Ask your boss for air- conditioning or fans and open windows where possible. Keep windows shaded with blinds and if possible move your working position out of direct sunlight. Have plenty of breaks during the day to get cold drinks and cool down.

According to the Department of Health: "These precautionary measures will help increase protection from heat exhaustion and sunstroke as well as food poisoning and skin cancer."

A Department of Health spokesperson said:

"This week's temperatures are unusually high and people need to take extra care. The tips issued today are common sense precautions and will help people enjoy the weather whilst protecting themselves from the dangerous, and potentially fatal, effects of these temperatures."

Advice compiled the advice in consultation with the Food Standards Agency, Health and Safety Executive, and Meteorological Office.

For more information on sunstroke, see NHS Direct