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.

Overhydration: Types, Symptoms, and Treatments

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Drinking too much water can be dangerous. Some health conditions can also make your body retain too much water, regardless of how much you drink.

All of the major systems of your body depend on water to work properly. Having enough water helps your body:

• regulate temperature
• prevent constipation
• flush out waste products
• perform all major bodily functions

Most people, especially those who exercise in hot weather, are concerned about not drinking enough water. However, it’s possible to have too much water in your body. This can cause water toxicity. This is when your body’s water is more than your kidneys can excrete. It can lead to a dangerous electrolyte imbalance.

Read on to learn how this can happen, how much water is too much, how to recognize the signs, and what to do.

You can become overhydrated in two ways: By drinking too much water or if your kidneys retain too much water.

In both cases, overhydration can lead to water toxicity, also known as water poisoning. Your body’s water volume becomes too large for your kidneys to excrete, which can cause the electrolytes in your body to dilute.

When the amount of sodium (salt) becomes too diluted, you develop hyponatremia. This is the main concern of overhydration. When the sodium levels in your body are greatly reduced, fluids move inside your cells, leading to inflammation.

Increased water intake

This occurs when you drink more water than your kidneys can remove from your urine. Endurance athletes, such as those who run marathons and triathlons, sometimes drink too much water before and during an event. In healthy people, athletes are at the highest risk for overhydration.

Certain conditions and drugs can also cause increased water intake by making you extremely thirsty. These include:

• schizophrenia
• MDMA (commonly known as ecstasy)
• antipsychotic drugs
• diuretics

Retaining water

This occurs when your body can’t get rid of water properly. Several medical conditions can cause your body to retain water. These include:

• congestive heart failure (CHF)
• liver disease
• kidney problems
• syndrome of inappropriate antidiuretic hormone
• nonsteroidal anti-inflammatory drugs
• uncontrolled diabetes

The Institute of Medicine has established guidelines for adequate water intake. They recommend that a healthy adult drink 78–100 ounces (oz) (about 9­–13 cups) of fluids per day on average. It’s also important to remember that the food you eat, such as vegetables or fruit, also contains water.

That being said, the amount of water you need to drink can vary and should roughly equal the amount your kidneys release. Children and adolescents may have lower requirements than adults.

It’s also important to remember that water needs vary with sex, weather, activity level, and overall health. Common situations such as extreme heat, significant activity, and illness with fever may require more fluid intake than average.

You may not recognize symptoms of overhydration in its early stages. However, urine is a good indicator of hydration status in a healthy person.

Pale yellow urine that looks like lemonade is a good goal. Darker urine means you need more water. Colorless urine means you are overhydrated.

If you get hyponatremia from water toxicity, you’ll likely experience the following:

• nausea and vomiting
• headache due to pressure on the brain
• changes in mental state, such as confusion or disorientation
• drowsiness
• muscle cramps

Ultimately the swelling of brain cells will cause your central nervous system to malfunction. Without treatment, you can experience seizures, enter into a coma, and ultimately die.

Death from drinking too much water in healthy people is rare, but it can happen, especially in athletes. Usually, water toxicity occurs along with an underlying medical condition that causes the kidneys to retain fluid.

Can drinking too much water be fatal? Learn more.

Water toxicity from overhydration is more common among endurance athletes who drink large amounts of water before and during exercise. It has been reported among:

• people who run marathons and ultramarathons (races longer than 26.2 miles)
• ironman triathletes
• endurance cyclists
• rugby players
• elite rowers
• military members involved in training exercises
• hikers

This condition is also more likely in people with kidney or liver disease. It can also affect people with heart failure.

A doctor will ask about your medical history to determine if your symptoms are caused by water toxicity, hyponatremia, or another condition.

The doctor will also perform a physical examination, and they may order blood and urine tests to check the level of sodium and other markers in your body.

They may observe you for a time to see how much fluid you are taking in versus how much you release in urine or stool. They may measure your weight to watch for changes indicative of insufficient fluid loss.

If you have more obvious water toxicity symptoms, the doctor may identify these sooner and initiate treatment.

How you’re treated depends on whether you show symptoms of water toxicity and what caused the condition. Treatments may include:

• cutting back on your fluid intake
• taking diuretics to increase the amount of urine you produce
• treating the condition that caused the overhydration
• stopping any medications causing the problem
• replacing sodium in severe cases

Endurance athletes can reduce the risk of water toxicity from overhydration by weighing themselves before and after a race. This helps determine how much water they have lost and need to replenish.

While there are different guidelines, they generally recommend drinking 14-22 oz of fluid about two-three hours before exercise or physical activity.

If exercising longer than an hour, sports beverages are also an option. These drinks contain sugar and electrolytes such as sodium and potassium, which you lose in sweat. Let thirst also guide you when exercising. If you’re thirsty, drink more.

However, if you are an endurance athlete or planning on starting an endurance training program, you want to talk with your doctor to get hydration advice tailored specifically to you.

The following are the answers to some common questions about overhydration.

How much water a day is overhydration?

Healthy adult kidneys can eliminate about 1 liter (l) or 0.2 gallons (gl) of water per hour. Although no specific amount of fluids can cause overhydration for a person, it’s a good idea not to drink more than your kidneys can handle.

Kidneys of children and older people may be less efficient at removing water, so you should consult with a primary care doctor or pediatrician to understand the appropriate amount. Some doctors recommend that the number of daily cups of water a child drinks should equal their age.

Can overhydration cause permanent damage?

Drinking too many fluids can cause water toxicity by diluting your body’s sodium and other electrolytes, which may cause your cells to swell, including the cells in your brain. This is a life threatening condition. If left untreated, it may cause permanent brain damage and death.

How long does it take to recover from overhydration?

Your recovery will depend on the severity of your symptoms. If you progress to water toxicity, you will need to be hospitalized. If you experience any symptoms associated with overhydration, contact your doctor.

Overhydration due to drinking too much water causes water toxicity, an electrolyte imbalance that can cause symptoms ranging from nausea and headache to unconsciousness and coma.

To avoid overhydrating, try to drink no more than about 9­–13 cups of fluids per day. If you have a medical condition such as diabetes, CHF, or kidney disease, talk with your doctor about the best treatments.

Also, contact your doctor if you’re unusually thirsty. This could signify a medical problem that needs to be treated.

Dehydration (Adult): Causes, Symptoms, Signs, Treatment, Diagnosis, Prevention

Overview

Dehydration happens when your body loses more water than it takes in. You naturally lose water daily through urination, perspiration, even breathing. Normally, the water that is contained in what we drink or eat replaces the fluid that we have lost. Dehydration becomes a problem when the loss becomes excessive, say due to vomiting or diarrhea, and you cannot replace the lost water with sufficient fluid. It can also happen as a result of excessive sweating during physical work on a hot day without adequate access to water. Not getting enough water can cause low blood pressure, weakness, dizziness, fatigue, even nausea. The greater the lack of water, the higher the risk of serious complications. Severe dehydration can lead to problems such as kidney failure, confusion, coma, or shock.

What to expect

Your body needs 2 to 3 liters of fluid daily. Not getting this amount of fluid, or an increased need for it as a result of illness or increased physical activity, can cause mild dehydration. Mild dehydration can be cured by drinking extra water, other drinks, or sucking on ice cubes or frozen juice. If the loss of water is significant and the person has not received or cannot receive enough fluid to rehydrate, they may need intravenous fluids.

Condition may worsen due to

Hard work; high ambient temperature; lack of water; caffeine; alcohol; taking diuretics.

Diagnosis

A physician can predominantly diagnose dehydration based on certain signs and symptoms, such as low blood pressure, little or no urination, sunken eyes, and lack of skin elasticity. Your doctor may order other tests, such as a blood or urine test. It can also assess a person’s mental state to help determine how serious the condition is.

Treatment

The choice of treatment for dehydration depends on the person’s age and how severe the dehydration is. The first step is to restore the lost volume of fluid. To get rid of mild to moderate dehydration, it is enough to drink plenty of fluids. When the case is severe, you may need intravenous fluids. If dehydration is the result of an illness, the doctor will also treat the illness or adjust medication to control symptoms and reduce the amount of fluid that is lost.

Self-medication

When mildly dehydrated, drink water, suck on frozen juice, or drink sports drinks such as Gatorade. If needed, take medicines for diarrhea, vomiting, or fever to reduce fluid loss associated with these problems.

When to see a doctor

Call your doctor if:

– you are vomiting for more than 24 hours or have diarrhea for more than 2 days

– you notice excessive urination

– you produce very little or no urine in 8 hours

– you have other symptoms of dehydration during diarrhea

– you feel too weak

– you have a temperature above 38. 3 ^about C

Remember: Severe dehydration is life threatening! Call 103 if you have at least one of these symptoms:

– temperature above 39.4 ^o C

– confusion, drowsiness or headache

– convulsions or loss of consciousness

– pain in the chest or abdomen, difficulty breathing

– no urination in the last 12 hours

Risk factors

Illnesses that cause fever, vomiting, or diarrhea; diabetes; excessive exercise; heat stroke or excessive exposure to heat; inability to drink fluids for any reason.

What is the danger of dehydration and how to help the body

March 10, 2023
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You can live without food for about a month, and without water for a week. Dehydration is a significant lack of water in the body. In the best case, it will lead to malaise and poor health, and in the worst case, to death.

Types and causes of dehydration

The causes of dehydration are varied, but most often these are diseases that are accompanied by sweating, vomiting and diarrhea. There is an excessively high and rapid loss of fluid.

It is also affected by malnutrition, exercise, hot climates and debilitating diets.

You need to understand that dehydration is different. If at 1% you feel intense thirst, headache and general malaise, then at 10% you will have convulsions and body cells will begin to die. Death occurs at 20% dehydration. It is especially dangerous for children, because of the small weight, the symptoms develop much faster.

Dehydration can be divided into several conditional stages. With a lung, there are still no disturbances in the processes in the body, however, a person begins to lose weight, get tired and be distracted.

In moderate cases, the initial symptoms are aggravated, the mucous membranes become dry, the eyes sink, tachycardia is detected. Changes in blood pressure (BP).

Severe dehydration threatens with hallucinations, loss of consciousness. There are problems with urination, the skin becomes bluish, blood pressure becomes significantly lower than normal. This condition is a direct threat to health and life.

How to avoid dehydration?

To do this, you need to maintain your water balance in the norm.

During illness, especially in cases of poisoning, you should drink plenty of pure water.

With increased physical activity and in hot weather, it is also necessary to increase fluid intake. The use of watery vegetables – cucumbers, tomatoes, celery will also help.

Thirst cannot be tolerated. If such a feeling appears, you should not ignore it. A good prevention is the daily use of 1.5 liters of water.

Staying in hot and stuffy rooms should also be avoided.