Dehydration – Illnesses & conditions

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1. 1.

   About dehydration

2. 2.

   Symptoms of dehydration

3. 3.

   Causes of dehydration

4. 4.

   Treating dehydration

5. 5.

   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, it upsets 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 of dehydration include:

• feeling thirsty and lightheaded
• a dry 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 body is affected even 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 in hot weather) and your diet can contribute to dehydration.

You can also become dehydrated as a result of an illness, such as persistent vomiting and diarrhoea, or sweating 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 you’re dehydrated, drink plenty of fluids such 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 you’re finding it difficult to keep water down because you’re vomiting, try drinking small amounts more frequently.

Infants and small children who are dehydrated shouldn’t be given large amounts of water alone as the main replacement fluid. This is because 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 doesn’t go away after a few seconds

You should also contact your GP if your baby has had six 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 body’s way of trying 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 urine infrequently (less than three or four times a day)

Dehydration can also lead to a loss of strength and stamina. It’s a main cause of heat exhaustion.

You should be able to reverse dehydration at this stage by drinking more 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 has had six or more episodes of diarrhoea in 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 service or NHS 24 111 service straight 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 doesn’t 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

If severe dehydration 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 dehydration can depend 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, it’s important to drink regularly to replace lost fluids. It doesn’t 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, you’re 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

Who’s 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 they’re becoming dehydrated and need to drink 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

Hyponatremia

It’s possible to become overhydrated while exercising. This is known as hyponatremia and it’s 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, take them to see your GP as soon as possible. They’ll be able to recommend appropriate treatments, such as those outlined below.

Give your baby plenty of liquids, such as breastmilk or formula. It can often be better to give them smaller amounts of fluid more frequently.

Don’t dilute your baby’s formula (if you use it). Babies who are formula-fed and those on solids can be given extra water.

Avoid giving your baby fruit juice, particularly if they have diarrhoea and vomiting, because it can make 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 milk and water) will help to replace lost fluids, salts and sugars.

Infants and children

Infants and children who are dehydrated shouldn’t 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 to use 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

When you’re dehydrated, you lose sugar and salts, as well as water. Drinking a rehydration solution will 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

Seek immediate medical help 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 or using a 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 you’re well hydrated.

Drink regularly

If you’re active, or if the weather is particularly hot, there’s a greater risk that you will become dehydrated. To prevent becoming dehydrated, you should increase your fluid intake.

As different people sweat at different rates, it’s very difficult to provide specific recommendations about how much fluid you should drink. However, you should drink more than normal while exercising, and it’s particularly important to keep well hydrated if you’re exercising in warm conditions. This is because 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 the amount of sodium (salt) in your blood. This can lead to a serious and potentially fatal condition called hyponatremia. If you start to feel discomfort and bloating from drinking, stop drinking and allow time to recover.

Illness

If you, your child or someone you are caring for is ill, particularly with a fever, vomiting or diarrhoea, there’s a high risk of becoming dehydrated, so it’s 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, it’s 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.

Dehydration – Symptoms & causes

Overview

Dehydration occurs when you use or lose more fluid than you take in, and your body doesn’t have enough water and other fluids to carry out its normal functions. If you don’t replace lost fluids, you will get dehydrated.

Anyone may become dehydrated, but the condition is especially dangerous for young children and older adults.

The most common cause of dehydration in young children is severe diarrhea and vomiting. Older adults naturally have a lower volume of water in their bodies, and may have conditions or take medications that increase the risk of dehydration.

This means that even minor illnesses, such as infections affecting the lungs or bladder, can result in dehydration in older adults.

Dehydration also can occur in any age group if you don’t drink enough water during hot weather — especially if you are exercising vigorously.

You can usually reverse mild to moderate dehydration by drinking more fluids, but severe dehydration needs immediate medical treatment.

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Symptoms

Thirst isn’t always a reliable early indicator of the body’s need for water. Many people, particularly older adults, don’t feel thirsty until they’re already dehydrated. That’s why it’s important to increase water intake during hot weather or when you’re ill.

The signs and symptoms of dehydration also may differ by age.

Infant or young child

• Dry mouth and tongue
• No tears when crying
• No wet diapers for three hours
• Sunken eyes, cheeks
• Sunken soft spot on top of skull
• Listlessness or irritability

Adult

• Extreme thirst
• Less frequent urination
• Dark-colored urine
• Fatigue
• Dizziness
• Confusion

When to see a doctor

Call your family doctor if you or a loved one:

• Has had diarrhea for 24 hours or more
• Is irritable or disoriented and much sleepier or less active than usual
• Can’t keep down fluids
• Has bloody or black stool

Causes

Sometimes dehydration occurs for simple reasons: You don’t drink enough because you’re sick or busy, or because you lack access to safe drinking water when you’re traveling, hiking or camping.

Other dehydration causes include:

• Diarrhea, vomiting. Severe, acute diarrhea — that is, diarrhea that comes on suddenly and violently — can cause a tremendous loss of water and electrolytes in a short amount of time. If you have vomiting along with diarrhea, you lose even more fluids and minerals.
• Fever. In general, the higher your fever, the more dehydrated you may become. The problem worsens if you have a fever in addition to diarrhea and vomiting.
• Excessive sweating. You lose water when you sweat. If you do vigorous activity and don’t replace fluids as you go along, you can become dehydrated. Hot, humid weather increases the amount you sweat and the amount of fluid you lose.
• Increased urination. This may be due to undiagnosed or uncontrolled diabetes. Certain medications, such as diuretics and some blood pressure medications, also can lead to dehydration, generally because they cause you to urinate more.

Risk factors

Anyone can become dehydrated, but certain people are at greater risk:

• Infants and children. The most likely group to experience severe diarrhea and vomiting, infants and children are especially vulnerable to dehydration. Having a higher surface area to volume area, they also lose a higher proportion of their fluids from a high fever or burns. Young children often can’t tell you that they’re thirsty, nor can they get a drink for themselves.
• Older adults. As you age, your body’s fluid reserve becomes smaller, your ability to conserve water is reduced and your thirst sense becomes less acute. These problems are compounded by chronic illnesses such as diabetes and dementia, and by the use of certain medications. Older adults also may have mobility problems that limit their ability to obtain water for themselves.
• People with chronic illnesses. Having uncontrolled or untreated diabetes puts you at high risk of dehydration. Kidney disease also increases your risk, as do medications that increase urination. Even having a cold or sore throat makes you more susceptible to dehydration because you’re less likely to feel like eating or drinking when you’re sick.
• People who work or exercise outside. When it’s hot and humid, your risk of dehydration and heat illness increases. That’s because when the air is humid, sweat can’t evaporate and cool you as quickly as it normally does, and this can lead to an increased body temperature and the need for more fluids.

Complications

Dehydration can lead to serious complications, including:

• Heat injury. If you don’t drink enough fluids when you’re exercising vigorously and perspiring heavily, you may end up with a heat injury, ranging in severity from mild heat cramps to heat exhaustion or potentially life-threatening heatstroke.
• Urinary and kidney problems. Prolonged or repeated bouts of dehydration can cause urinary tract infections, kidney stones and even kidney failure.
• Seizures. Electrolytes — such as potassium and sodium — help carry electrical signals from cell to cell. If your electrolytes are out of balance, the normal electrical messages can become mixed up, which can lead to involuntary muscle contractions and sometimes to a loss of consciousness.
• Low blood volume shock (hypovolemic shock). This is one of the most serious, and sometimes life-threatening, complications of dehydration. It occurs when low blood volume causes a drop in blood pressure and a drop in the amount of oxygen in your body.

Prevention

To prevent dehydration, drink plenty of fluids and eat foods high in water such as fruits and vegetables. Letting thirst be your guide is an adequate daily guideline for most healthy people.

People may need to take in more fluids if they are experiencing conditions such as:

• Vomiting or diarrhea. If your child is vomiting or has diarrhea, start giving extra water or an oral rehydration solution at the first signs of illness. Don’t wait until dehydration occurs.
• Strenuous exercise. In general, it’s best to start hydrating the day before strenuous exercise. Producing lots of clear, dilute urine is a good indication that you’re well-hydrated. During the activity, replenish fluids at regular intervals and continue drinking water or other fluids after you’re finished.
• Hot or cold weather. You need to drink additional water in hot or humid weather to help lower your body temperature and to replace what you lose through sweating. You may also need extra water in cold weather to combat moisture loss from dry air, particularly at higher altitudes
• Illness. Older adults most commonly become dehydrated during minor illnesses — such as influenza, bronchitis or bladder infections. Make sure to drink extra fluids when you’re not feeling well.

Dehydration in children: how to prevent and recognize

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Dehydration is a situation when the human body loses a large amount of fluid necessary for the functioning of vital organs.

Why are children at risk and more susceptible to dehydration?

Children, along with the elderly, are at risk and more than susceptible to dehydration due to a combination of several factors:

First because they are a group of people who, due to their age, are more likely to suffer from infections, which can cause fever and gastrointestinal symptoms such as vomiting or diarrhea, which lead to fluid loss in the body. However, dehydration can occur not only with gastroenteritis, but with other infections, such as respiratory (colds, sinusitis, pneumonia, bronchitis) or urinary tract infections.

Second , because in the child’s body a higher percentage of water . In a newborn, for example, about 70% of his body weight is water. This percentage gradually decreases as the child grows up, until it reaches 50-60% in adulthood, depending on age and gender.

Thirdly, , because with a smaller body volume, the ratio between body surface and weight is higher than . This means that in children, the loss of moisture through the skin and mucous membranes by evaporation is proportionally greater than in adults.

It should also be added that the compensation mechanisms that the body starts when it begins to lose moisture, are still insufficiently developed at an early age of life. The ability to concentrate urine and thereby reduce water loss is less in a newborn than in a school-age child or adult, making young children more vulnerable in these situations.

Finally, in the case of young children, they have limited access to fluids because they0009 cannot drink on their own and depend on adults to provide them with water to drink in situations of dehydration due to illness or hot weather.

Thus, newborns and infants are most at risk of dehydration.

Dehydration and medications for chronic conditions

Although children often need to take medications for chronic illnesses, be aware that some medications can exacerbate symptoms of dehydration . An obvious example of this type of medication is the diuretics (furosemide, spironolactone…) which increase the loss of water through the urine to compensate for problems with the heart, kidneys, etc.

It should also be taken into account that if a child is taking any medications for chronic diseases, their blood levels, as well as their therapeutic effects (both beneficial and adverse), may temporarily change when a situation of dehydration occurs. This does not mean that we should be worried, but we should consider it, for example, in the case of children receiving antiepileptic drugs , since in a situation of dehydration, the drugs will no longer work and the epilepsy may temporarily decompensate.

What are the symptoms of dehydration?

On the one hand, symptoms are associated with the loss of fluid and electrolytes (mineral salts), and on the other hand, with compensation mechanisms that the body triggers to restore the loss of moisture. Some of the symptoms of dehydration:

1. Deterioration in general well-being
2. Dry mouth, lack of saliva or whitish foamy saliva
3. Paleness
4. Sunken eyes
5. Abnormal breathing 9 0010
6. Crying without tears
7. Reduced urge to urinate
8. Increased thirst

tria, clinical dehydration scale …). If one or more symptoms are observed in a child, it is important to see a doctor as soon as possible .

How can dehydration be prevented?

In the situations of symptoms of the disease described above (fever, vomiting, diarrhea), it is very important to offer the child plenty of fluids to maintain a normal state of hydration. In addition to water, the liquid you offer your child should contain glucose (sugar) and mineral salts because not only water is lost during vomiting and diarrhea, but also sugar and minerals such as sodium, potassium and chlorine. These substances are vital for maintaining the functioning of the organs and systems of our body. Often their levels change in situations of dehydration (hyper or hyponatremia, hypoglycemia …), which can aggravate the symptoms of the disease. Therefore , it is recommended to replenish fluid loss by using Oral Rehydration Serum, which can be purchased at pharmacies.

In other situations where water loss in the body is increased due to perspiration, such as during summer and prolonged physical activity, it is recommended to use water as the main rehydrator , accompanied by foods that contain carbohydrates, mineral salts and water, such as fruits. Sports isotonic drinks are not needed for children and their habitual use can be detrimental to health.

How to suspect dehydration and how it threatens the body

Health

2 February

It is better to drink before thirst appears.

What is dehydration

Dehydration is a condition in which the body loses more fluid than it takes in.

The human body is 55-78% water. It is involved in all processes, so the loss of even 1.5% causes headaches, dizziness and fatigue. The best way to prevent dehydration is to drink before you feel thirsty. But it is very difficult to make up for the loss of fluid in some diseases. Because of this, dehydration can even lead to death.

Why dehydration occurs

Dehydration occurs when a person does not drink enough water or loses it too quickly. Possible reasons for this situation:

• sweating on a hot day or with a fever;
• severe vomiting;
• prolonged diarrhoea;
• frequent urination when taking diuretics.

Who is more likely to get dehydrated

Anyone can get dehydrated, but the most common ones are:

• babies because they cannot report thirst and their condition;
• taking diuretics;
• who have had severe diarrhea or who often have intestinal problems;
• older people because they already have less water in their bodies, feel less thirsty and take more diuretics because of heart disease;
• people with diabetes due to more frequent urination;
• athletes — against the background of intense training;
• drinking too much alcohol;
• those who have spent a lot of time in the sun or in a hot environment such as a sauna.

What complications can dehydration lead to

Since all organs need water, the body suffers without it: there is less blood. Therefore, the heart is forced to work harder, and the vessels of the brain narrow. The latter affects memory and coordination.

If there are not enough salts and minerals, convulsions and interruptions in the work of the heart may begin.

And if the blood becomes critically low, hypovolemic shock may develop. With it, organs can be irreversibly damaged, and a person can die.

What are the signs of dehydration

Thirst seems to be the most obvious sign, but it’s not that simple. Many people, especially the elderly, don’t feel dehydrated until they become dehydrated enough. Therefore, you need to drink before you feel like it, and increase the amount of water in hot weather, during sports and when you are sick.

You can notice dehydration by symptoms such as:

• dry mouth;
• headache;
• dizziness;
• drowsiness;
• decreased amount of urine (babies keep diapers dry longer).

What to do when you’re dehydrated

When you’re dehydrated, you need to drink water. If it does not linger and “asks back”, start with very small portions, for example, drink from a spoon. Relief usually comes quickly.

Avoid fruit juices, as they are high in sugar and fruit acids and can aggravate indigestion. Drinks with caffeine and alcohol are also not recommended, because they increase urination and, conversely, draw out water.

With severe sweating, vomiting and diarrhea, in addition to fluid, the body loses salts and minerals that need to be replenished. In such a situation, a large volume of water will not help, but will only dilute the blood, which can cause heart failure, convulsions and other problems.

Therefore, with large fluid losses, it is better to drink pharmacy solutions of electrolytes, and during intense training – sports drinks with salts.

Babies should not be given water to avoid water intoxication. So it is better to apply to the chest more often. If the child receives the mixture, then in no case should it be diluted further. If dehydration is suspected, try giving a little water from a spoon.

In severe cases, if drinking does not seem to help, or if vomiting and diarrhea persist, you will need medical attention.

When to call an ambulance

Severe dehydration can lead to serious consequences. Therefore, sometimes with dehydration, urgent medical attention is needed.

For an adult and a child who already speaks well

The following symptoms can be considered dangerous:

• feeling extremely tired;
• disorientation in space;
• dizziness when standing up that does not go away within a few seconds;
• dark yellow urine;
• infrequent urge to urinate;
• rapid breathing and palpitations;
• reddened and hot skin;
• fever;
• convulsions;
• hallucinations;
• altered mental state.

To a small child

Very young children cannot tell how they feel, so you need to monitor the following signs:

• child seems sleepy;
• diaper stays dry longer than usual;
• urine is darker and smells stronger;
• the child is breathing rapidly and his heart is beating very fast;
• few or no tears during crying;
• the fontanel sinks, that is, the membrane on the head, as it were, is pulled inward;
• fever present;
• convulsions;
• skin red and hot.