Dehydration occurs when your body loses too much water; upsetting the balance of minerals in your body, and altering the way that your organs function.
Sweating a lot can also make you dehydrated, as can sunstroke (from spending too much time in the hot sun) and drinking too much alcohol.
Illnesses that cause a fever, diarrheoa or vomiting can also increase your risk of dehydration, and some medications (diuretics) are known to make you lose a lot of fluids.
Dehydration is often split into 3 separate ‘types’ or categories, defined by the amount of body weight that you have lost due to fluid loss:
- mild dehydration -- when you have lost 3-5% of your total body weight
- moderate dehydration -- when you have lost 5-9% loss of body weight
- severe dehydration -- when you lose more than 10% of your body weight
Mild and moderate dehydration can normally be treated by replacing lost salts and fluids at home, while severe dehydration is normally a serious medical emergency that needs to be treated in hospital.
How do you treat dehydration?
Treating mild or moderate dehydration
You can manage most cases of mild or moderate dehydration at home.
You should start by drinking plenty of extra fluids, but it is important to remember that drinking plain water may not be enough to replenish the salts, sugars and minerals that your body has lost.
If you think that you might be moderately dehydrated, you may want to consider taking an oral rehydration solution (often available as a sachet or packet from your local pharmacy).
You could also try drinking a flat fizzy drink, such as cola, and eating a salty snack like a packet of crisps.
Some experts recommend that you drink diluted squash, fruit juice or a flavoured sports drink to replenish your electrolytes, but it's important to remember that some of these options may contain a lot of extra sugar.
If you’re struggling to drink large amounts of fluid without feeling sick or nauseous, you may find that it helps to take lots of small sips more often, instead of trying to gulp down a drink.
If your symptoms do not improve, you should try to visit a doctor as soon as possible.
Treating severe dehydration
Chronic or severe dehydration can be a medical emergency. You should go straight to the nearest emergency room if you are feeling unusually tired, confused or disoriented.
The doctor may put you on an intravenous drip to replenish any lost salts, and they may also want to order tests to find out why you are dehydrated.
You should also seek emergency medical attention if:
- you get dizzy when you stand up, and your dizziness doesn't go away after a few seconds
- you have not peed all day
- your pulse is rapid or weak
- you are having fits or seizures
What are the symptoms of dehydration?
You may be able to tell whether you are dehydrated by looking at the colour of your pee.
Passing pale white or yellow urine normally means that you are well hydrated, while dark yellow urine can be a sign that your body is dehydrated.
Other symptoms of mild or moderate dehydration include:
- dryness of the mouth, lips and tongue
- feeling thirsty, tired, light-headed or dizzy
- peeing less than 4 times a day
- having difficulty concentrating on things
Some people are less likely to feel thirsty when they are dehydrated. This is particularly true of older people and young children.
Can I prevent dehydration?
Prevention is always easier than cure.
To try and stop yourself from getting dehydrated, try to drink 6-8 glasses of fluid every day, and eat plenty of water-rich foods. Soup, cucumber and ice cream of fruits like melon can all help you to replenish lost fluids.
You can also help to prevent dehydration by drinking extra fluids when you’re hot, have an illness that causes vomiting or diarrhoea, or doing something that makes you sweat more than usual.