Dehydration

Dehydration - Illnesses & conditions | NHS inform Home Illnesses and conditions Symptoms and self-help Tests and treatments Healthy living Care, support and rights Scotlands Service Directory 0 Home Illnesses and conditions Nutritional Dehydration Dehydration About dehydration Symptoms of dehydration Causes of dehydration Treating dehydration Preventing dehydration About dehydration Dehydration occurs when your body loses more fluid than you take in. When the normal water content of your body is reduced, itupsets the balance of minerals (salts and sugar) in your body, which affects the way it functions. Water makes up over two-thirds of the healthy human body. It lubricates the joints and eyes, aids digestion,flushes out waste and toxins, and keeps the skin healthy. Some of the early warning signs ofdehydration include: feelingthirsty and lightheaded adry mouth tiredness having dark coloured, strong-smelling urine passing urine less often than usual A baby may be dehydrated if they: have a sunken soft spot (fontanelle) on their head have few or no tears when they cry have fewer wet nappies are drowsy The bodyis affectedeven when you lose a small amount of fluid. Read more about the symptoms of dehydration What causes dehydration? Dehydration is usually caused by not drinking enough fluid to replace what we lose. The climate, the amount of physical exercise you are doing (particularly inhot weather)and your diet can contribute to dehydration. You can alsobecome dehydrated as a result of an illness, such aspersistent vomiting and diarrhoea, orsweating from a fever. Read more about the causes of dehydration Who is at risk from dehydration? Anyone can become dehydrated, but certain groups are particularly at risk. These include: babies and infants  they have a low body weight and are sensitive to even small amounts of fluid loss older people  they may be less aware that they are becoming dehydrated and need to keep drinking fluids people with a long-term health condition  such as diabetes or alcoholism athletes  they can lose a large amount of body fluid through sweat when exercising for long periods What to do If youre dehydrated, drink plenty of fluidssuch as water, diluted squash or fruit juice. These are much more effective than large amounts of tea or coffee. Fizzy drinks may contain more sugar than you need and may be harder to take in large amounts. If youre finding it difficult to keep water down because youre vomiting,try drinking small amounts more frequently. Infants and small children who are dehydrated shouldnt be given large amounts of water alone as the main replacement fluid. This isbecause it can dilute the already low level of minerals in their body too much and lead to other problems. Instead, they should be given diluted squash or a rehydration solution (available from pharmacies). You might find a teaspoon or syringe can be helpful for getting fluid into a young child. If left untreated, severe dehydration can be serious and cause fits (seizures), brain damage and death. Read more about treating dehydration When to see your GP See your GP if your symptoms continue, despite drinking plenty of fluids, or if you think your baby or toddler is dehydrated. If your GP suspects dehydration, you may have a blood test or a urine test to check the balance of salts (sodium and potassium) in your body. Contact your GP, out-of-hours service or NHS 24 111 service straight away if you have any of the following symptoms: extreme thirst feeling unusually tired (lethargic) or confused not passing urine for eight hours rapid heartbeat dizziness when you stand up that doesnt go away after a few seconds You should also contact your GP if your baby has hadsix or more episodes of diarrhoea in the past 24 hours, or if they have vomited three times or more in the past 24 hours. Symptoms of dehydration Dehydration can be mild, moderate or severe, depending on how much of your body weight is lost through fluids. Two early signs of dehydration are thirst and dark-coloured urine. This is the bodys way oftrying to increase water intake and decrease water loss. Other symptoms may include: dizziness or light-headedness headache tiredness dry mouth , lips and eyes passing small amounts of urineinfrequently (less than three or fourtimes a day) Dehydration canalsolead toaloss ofstrength and stamina. Itsa maincause of heat exhaustion. You should be able to reverse dehydration at this stageby drinkingmore fluids. If dehydration is ongoing (chronic), it can affect your kidney function and increase the risk of kidney stones . It can also lead to muscle damage and constipation . When to see your GP See your GP if your symptoms continue despite drinking fluids, or if you suspect that your baby or toddler is dehydrated. You should also contact your GP if your baby hashadsix or more episodes of diarrhoeain the past 24 hours, or if they have vomited three times or more in the past 24 hours. If dehydration is suspected, you may be given a blood test or a urine test to check the balance of salts (sodium and potassium) in your body. Severe dehydration If dehydration is left untreated, it can become severe. Severe dehydration is a medical emergency and requires immediate medical attention. Contact your GP,out-of-hours serviceor NHS 24 111 servicestraight away if you have any of the following symptoms: feeling unusually tired (lethargic) or confused, and you think you may be dehydrated dizziness when you stand up that doesnt go away after a few seconds not passing urine for eight hours a weak pulse a rapid pulse fits (seizures) a low level of conciousness Ifseveredehydration is not treated immediately, it can lead to complications. This level of dehydration needs hospital treatment and you will be put on a drip to restore the substantial loss of fluids. Dehydration in babies A baby may be dehydrated if they have: a sunken soft spot (fontanelle) on their head few or no tears when they cry a dry mouth fewer wet nappies dark yellow urine drowsiness fast breathing cold and blotchy-looking hands and feet Read about how to treat dehydration in babies Causes of dehydration Dehydration is caused by not drinking enough fluid or by losing more fluid than you take in. Fluid is lost through sweat, tears, vomiting, urine or diarrhoea. The severity of dehydrationcandepend on a number of factors,such as climate, level of physical activity and diet. There are several causes of dehydration, which are described below. Illness Dehydration is often the result of an illness, such as gastroenteritis , where fluid is lost through persistent bouts of diarrhoea and vomiting. Sweating You can also become dehydrated if you sweat excessively after a fever, exercise, or carrying out heavy, manual work in hot conditions. In these situations, its important to drink regularly to replace lost fluids. It doesnt necessarily need to be hot for you to lose a significant amount of fluid from sweating. Children and teenagers are particularly at risk because they may ignore the symptoms of dehydration , or not know how to recognise and treat them. Alcohol Dehydration can also occur as a result of drinking too much alcohol .Alcohol is a diuretic, which means it makes you wee more. The headache associated with a hangover indicates that your body is dehydrated. You should try to drink plenty of water when you have been drinking alcohol. Diabetes If you have diabetes, youre at risk of becoming dehydrated because you have high levels of glucose in your bloodstream. Your kidneys will try to get rid of the glucose by creating more urine, so your body becomes dehydrated from going to the toilet more frequently. Read more about the different types of diabetes Whos at risk? The groups of people most at risk of dehydration are: babies and infants  their low body weight makes them sensitive to even small amounts of fluid loss older people  they may be less aware theyre becoming dehydrated and need to drink fluids people with a long-term health condition  such as diabetes oralcoholism athletes  they can lose a large amount of body fluid through sweat when exercising for long periods Hyponatremia Its possible to become overhydrated while exercising. This is known as hyponatremia and its caused by low sodium (salt) levels in the blood. It can occur if too much water is drunk over a short period of time. Hyponatremia sometimes affects athletes whose blood sodium level is reduced through sweat and then diluted by drinking large amounts of water. Symptoms of hyponatremia include nausea, vomiting and headache. In serious cases, the brain can swell, causing confusion, seizures, coma and, in rare cases, death. Treating dehydration The best way to treat dehydration is to rehydrate the body by drinking plenty of fluids, such as water, diluted squash or diluted fruit juice. A sweet drink can help to replace lost sugar, and a salty snack can help to replace lost salt. Babies If your baby is dehydrated, takethem to see your GPas soon as possible. Theyll be able to recommend appropriate treatments, such as those outlined below. Giveyour baby plenty of liquids, such as breastmilk or formula. It can often be better to give them smaller amounts of fluid more frequently. Dont dilute your babys formula (if you use it). Babies who are formula-fedand those on solids can begiven extra water. Avoid giving your baby fruit juice, particularlyif they have diarrhoea and vomiting,because it canmake it worse. Giving your baby regular sips(a few times an hour) of oral rehydration solution (ORS)in addition to their usual feed (breastmilk, formula milkand water) will help to replace lost fluids, salts and sugars. Infants and children Infants and children who are dehydrated shouldnt be given solely water, because it can dilute the already low level of minerals in their body and make the problem worse. Instead, they should have diluted squash or a special ORS (see below). If you or your child is finding it difficult to hold down fluids because of vomiting, take smaller amounts more frequently.You may find it easier touse a spoon or a syringe to give your child small amounts of fluid. Read more about vomiting in adults and vomiting in children and babies Oral rehydration solutions Whenyoure dehydrated, you lose sugar and salts, as well as water. Drinking a rehydration solutionwill enable you to re-establish the right balance of body fluids. The solution should contain a mixture of potassium and sodium salts, as well as glucose or starch. There are several different rehydration products available over the counter from pharmacies or on prescription from your GP, including solutions that are suitable for infants and children. Ask your GP or pharmacist for advice about the most suitable rehydration solution for you or your child. Severe dehydration Seekimmediatemedicalhelp if you suspect someone is severely dehydrated (see symptoms of severe dehydration ). They may need to be admitted to hospital for treatment. In particular, babies, infants and elderly people will need urgent treatment if they become dehydrated. Fluid may be given up the nose using a nasogastric tube orusinga saline drip into a vein (intravenously). This will provide essential nutrients faster than using solutions that you drink. If you have had bowel surgery, some rehydration solutions may not contain enough salt. In this instance, you will need a higher-strength solution. Your GP or surgeon can recommend a suitable rehydration solution for you. Preventing dehydration You should drink plenty of fluids to avoid becoming dehydrated. Most of the time, you can prevent dehydration by drinking water regularly throughout the day. Be guided by your thirst, but be aware that in hot weather, when exercising and during illness, you should drink more. Mild dehydration can be relieved by drinking more water and diluted fruit squash. If necessary, you can purchase oral rehydration solutions (ORS) from a pharmacy. As a guide, passing pale or clear-coloured urine (wee) is a good sign that youre well hydrated. Drinkregularly If youre active, or if the weather is particularly hot, theres a greater risk that you will become dehydrated. To prevent becoming dehydrated, you should increase your fluid intake. Asdifferent peoplesweat at different rates, its very difficult to provide specific recommendations about how much fluid you should drink. However, you should drink more than normal while exercising, and its particularly important tokeep well hydrated if youreexercising in warm conditions. This isbecause you will sweat more and fluid will be lost from your body more rapidly. Rarely, drinking more fluid than your body can process can reduce theamount of sodium (salt) in yourblood. This can lead to a serious and potentially fatal conditioncalled hyponatremia. If you start to feel discomfort and bloating from drinking, stop drinkingand allow time to recover. Illness If you, your child or someone you are caring for is ill, particularly witha fever, vomiting or diarrhoea , theres a high riskof becoming dehydrated, so its important to start replacing fluid as soon as possible. Advice for children There are no specific recommendations regarding the amount of water or other fluids that children need. However, its important for children to replace lost fluid, to prevent dehydration. Like adults, children lose more water when they are in hotter climates and when they are physically active. You should give your child healthy drinks as part of an overall healthy, balanced diet . Source: NHS 24 - Opens in new browser window Last updated: 21 November 2023 How can we improve this page? Help us improve NHS inform Thank You Your feedback has been received Dont include personal information e.g. name, location or any personal health conditions. Email Address e.g. you@example.com Message Maximum of 500 characters Send feedback Add this page to\n            Info For Me Other health sites NICE: Diarrhoea and vomiting in children under five (1) NHS inform About NHS inform Editorial policy Contact us Webchat Give feedback about NHS inform Info for Me tool Terms and conditions Privacy and cookies policy Freedom of information (FOI) Accessibility Other languages and formats  2023 NHS 24  v1.1.1.17852