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Dehydration

Overview

Dehydration occurs when your body loses too much fluid. This can happen when you stop drinking water or lose large amounts of fluid through diarrhea, vomiting, sweating, or exercise. Not drinking enough fluids can cause muscle cramps. You may feel faint. Usually your body can reabsorb fluid from your blood and other body tissues. But by the time you become severely dehydrated, you no longer have enough fluid in your body to get blood to your organs. You may go into shock, which is a life-threatening condition.

Dehydration can occur in anyone of any age. But it's most dangerous for babies, small children, and older adults.

Dehydration in babies and small children

Babies and small children have a greater chance of becoming dehydrated. That's because:

  • A greater portion of their bodies is made of water.
  • Children have a high metabolic rate, so their bodies use more water.
  • A child's kidneys don't conserve water as well as an adult's kidneys.
  • A child's natural defense system that helps fight infection (immune system) isn't fully developed. This makes them more likely to get an illness that causes vomiting and diarrhea.
  • Children often won't drink or eat when they aren't feeling well.
  • They depend on their caregivers to provide them with food and fluids.

Dehydration in older adults

Older adults have a greater chance of becoming dehydrated because they may:

  • Not drink because they don't feel thirsty.
  • Have kidneys that don't work well.
  • Choose not to drink because they can't control their bladders (incontinence).
  • Have physical problems or a disease that makes it:
    • Hard to drink or hold a glass.
    • Painful to get up from a chair.
    • Painful or exhausting to go to the bathroom.
    • Hard to talk or communicate to someone about their symptoms.
  • Take medicines, such as antihistamines or blood pressure medicines, that increase urine output.
  • Find it harder to eat a healthy diet.

Early symptoms of dehydration

Watch babies, small children, and older adults closely for the early symptoms of dehydration anytime they have an illness that causes high fever, vomiting, or diarrhea. These are the early symptoms of dehydration:

  • The mouth and eyes may be drier than usual.
  • The person may pass less urine than usual.
  • The person may feel cranky, tired, or dizzy.

Check Your Symptoms

Do you have a concern about dehydration?
Yes
Concern about dehydration
No
Concern about dehydration
How old are you?
Less than 3 months
Less than 3 months
3 months to 11 years
3 months to 11 years
12 years or older
12 years or older
Are you male or female?
Male
Male
Female
Female

The medical assessment of symptoms is based on the body parts you have.

  • If you are transgender or nonbinary, choose the sex that matches the body parts (such as ovaries, testes, prostate, breasts, penis, or vagina) you now have in the area where you are having symptoms.
  • If your symptoms aren’t related to those organs, you can choose the gender you identify with.
  • If you have some organs of both sexes, you may need to go through this triage tool twice (once as "male" and once as "female"). This will make sure that the tool asks the right questions for you.
Does your baby seem sick?
A sick baby probably will not be acting normally. For example, the baby may be much fussier than usual or not want to eat.
Yes
Baby seems sick
No
Baby seems sick
How sick do you think your baby is?
Extremely sick
Baby is very sick (limp and not responsive)
Sick
Baby is sick (sleepier than usual, not eating or drinking like usual)
Does your child have symptoms of shock?
Yes
Signs of shock
No
Signs of shock
Do you have symptoms of shock?
Yes
Symptoms of shock
No
Symptoms of shock
Do you think your baby may be dehydrated?
Yes
May be dehydrated
No
May be dehydrated
Are the symptoms severe, moderate, or mild?
Severe
Severe dehydration
Moderate
Moderate dehydration
Mild
Mild dehydration
Do you think your child may be dehydrated?
It can be harder to tell in a baby or young child than it is in an older child.
Yes
May be dehydrated
No
May be dehydrated
Are the symptoms severe, moderate, or mild?
The symptoms in a baby are different than the symptoms in an older child.
Severe
Severe dehydration
Moderate
Moderate dehydration
Mild
Mild dehydration
Is your child having trouble drinking enough to replace the fluids he or she has lost?
Little sips of fluid usually are not enough. The child needs to be able to take in and keep down plenty of fluids.
Yes
Unable to drink enough fluids
No
Able to drink enough fluids
Do you think you may be dehydrated?
Yes
May be dehydrated
No
May be dehydrated
Are the symptoms severe, moderate, or mild?
Severe
Severe dehydration
Moderate
Moderate dehydration
Mild
Mild dehydration
Are you having trouble drinking enough to replace the fluids you've lost?
Little sips of fluid usually are not enough. You need to be able to take in and keep down plenty of fluids.
Yes
Unable to maintain fluid intake
No
Able to maintain fluid intake
Do you think that a medicine could be causing the dehydration?
Think about whether the problem started after you began using a new medicine or a higher dose of a medicine.
Yes
Medicine may be causing dehydration
No
Medicine may be causing dehydration

Many things can affect how your body responds to a symptom and what kind of care you may need. These include:

  • Your age. Babies and older adults tend to get sicker quicker.
  • Your overall health. If you have a condition such as diabetes, HIV, cancer, or heart disease, you may need to pay closer attention to certain symptoms and seek care sooner.
  • Medicines you take. Certain medicines, such as blood thinners (anticoagulants), medicines that suppress the immune system like steroids or chemotherapy, herbal remedies, or supplements can cause symptoms or make them worse.
  • Recent health events, such as surgery or injury. These kinds of events can cause symptoms afterwards or make them more serious.
  • Your health habits and lifestyle, such as eating and exercise habits, smoking, alcohol or drug use, sexual history, and travel.

Try Home Treatment

You have answered all the questions. Based on your answers, you may be able to take care of this problem at home.

  • Try home treatment to relieve the symptoms.
  • Call your doctor if symptoms get worse or you have any concerns (for example, if symptoms are not getting better as you would expect). You may need care sooner.
HomeTreatment
RelatedInformation
WhereToGo

You can get dehydrated when you lose a lot of fluids because of problems like vomiting or fever.

Symptoms of dehydration can range from mild to severe. For example:

  • You may feel tired and edgy (mild dehydration), or you may feel weak, not alert, and not able to think clearly (severe dehydration).
  • You may pass less urine than usual (mild dehydration), or you may not be passing urine at all (severe dehydration).

Severe dehydration means:

  • Your mouth and eyes may be extremely dry.
  • You may pass little or no urine for 12 or more hours.
  • You may not feel alert or be able to think clearly.
  • You may be too weak or dizzy to stand.
  • You may pass out.

Moderate dehydration means:

  • You may be a lot more thirsty than usual.
  • Your mouth and eyes may be drier than usual.
  • You may pass little or no urine for 8 or more hours.
  • You may feel dizzy when you stand or sit up.

Mild dehydration means:

  • You may be more thirsty than usual.
  • You may pass less urine than usual.

Babies can quickly get dehydrated when they lose fluids because of problems like vomiting or fever.

Symptoms of dehydration can range from mild to severe. For example:

  • The baby may be fussy or cranky (mild dehydration), or the baby may be very sleepy and hard to wake up (severe dehydration).
  • The baby may have a little less urine than usual (mild dehydration), or the baby may not be urinating at all (severe dehydration).

Severe dehydration means:

  • The baby may be very sleepy and hard to wake up.
  • The baby may have a very dry mouth and very dry eyes (no tears).
  • The baby may have no wet diapers in 12 or more hours.

Moderate dehydration means:

  • The baby may have no wet diapers in 6 hours.
  • The baby may have a dry mouth and dry eyes (fewer tears than usual).

Mild dehydration means:

  • The baby may pass a little less urine than usual.

Shock is a life-threatening condition that may occur quickly after a sudden illness or injury.

Babies and young children often have several symptoms of shock. These include:

  • Passing out (losing consciousness).
  • Being very sleepy or hard to wake up.
  • Not responding when being touched or talked to.
  • Breathing much faster than usual.
  • Acting confused. The child may not know where he or she is.

Severe dehydration means:

  • The child's mouth and eyes may be extremely dry.
  • The child may pass little or no urine for 12 or more hours.
  • The child may not seem alert or able to think clearly.
  • The child may be too weak or dizzy to stand.
  • The child may pass out.

Moderate dehydration means:

  • The child may be a lot more thirsty than usual.
  • The child's mouth and eyes may be drier than usual.
  • The child may pass little or no urine for 8 or more hours.
  • The child may feel dizzy when he or she stands or sits up.

Mild dehydration means:

  • The child may be more thirsty than usual.
  • The child may pass less urine than usual.

A baby that is extremely sick:

  • May be limp and floppy like a rag doll.
  • May not respond at all to being held, touched, or talked to.
  • May be hard to wake up.

A baby that is sick (but not extremely sick):

  • May be sleepier than usual.
  • May not eat or drink as much as usual.

Shock is a life-threatening condition that may quickly occur after a sudden illness or injury.

Adults and older children often have several symptoms of shock. These include:

  • Passing out (losing consciousness).
  • Feeling very dizzy or lightheaded, like you may pass out.
  • Feeling very weak or having trouble standing.
  • Not feeling alert or able to think clearly. You may be confused, restless, fearful, or unable to respond to questions.

Many prescription and nonprescription medicines can cause dehydration. A few examples are:

  • Antihistamines.
  • Blood pressure medicines.
  • Chemotherapy.
  • Diuretics.
  • Laxatives.

Seek Care Today

Based on your answers, you may need care soon. The problem probably will not get better without medical care.

  • Call your doctor today to discuss the symptoms and arrange for care.
  • If you cannot reach your doctor or you don't have one, seek care today.
  • If it is evening, watch the symptoms and seek care in the morning.
  • If the symptoms get worse, seek care sooner.
HomeTreatment
RelatedInformation
WhereToGo

Call 911 Now

Based on your answers, you need emergency care.

Call 911 or other emergency services now.

Sometimes people don't want to call 911. They may think that their symptoms aren't serious or that they can just get someone else to drive them. Or they might be concerned about the cost. But based on your answers, the safest and quickest way for you to get the care you need is to call 911 for medical transport to the hospital.

Seek Care Now

Based on your answers, you may need care right away. The problem is likely to get worse without medical care.

  • Call your doctor now to discuss the symptoms and arrange for care.
  • If you cannot reach your doctor or you don't have one, seek care in the next hour.
  • You do not need to call an ambulance unless:
    • You cannot travel safely either by driving yourself or by having someone else drive you.
    • You are in an area where heavy traffic or other problems may slow you down.

Self-Care

In the early stages, you may be able to correct mild dehydration with home treatment. It's important to take action to prevent dehydration. Here are some things you can do.

  • Stop your activity.
  • Get out of direct sunlight.

    Lie down in a cool spot, such as in the shade or an air-conditioned area.

  • Prop up your feet.
  • Take off any extra clothes.
  • Drink plenty of fluids.

    Use an electrolyte replacement drink or sports drink to replace fluids and minerals.

  • Rest.

    Take it easy for 24 hours. Keep drinking a lot of fluids. You'll probably start feeling better within just a few hours. But it may take as long as a day and a half to completely replace the fluid that you lost.

Caring for a child

It's important to take action to prevent dehydration in children, ages 1 to 11 years. Use these tips if your child is dehydrated.

  • Give your child more fluids.

    Make sure that your child is drinking often. Frequent, small amounts work best.

  • Give your child cereal or flavored ice pops.

    Fluids can be replaced with cereal mixed with milk or water. Don't give your child fruit juice or soda pop. They contain too much sugar and not enough of the essential minerals (electrolytes) that are being lost. Diet soda pop lacks calories that your child needs.

  • Give your child an oral rehydration solution (ORS).

    If your child still isn't drinking enough fluids, you can try an ORS, such as Pedialyte. The amount of ORS your child needs depends on your child's age and size.

Caring for a baby

Don't wait until you see signs of dehydration in your newborn or baby younger than 1 year of age. These signs include your baby having fewer or no wet diapers and dry mouth and dry eyes (fewer tears than usual). Here are some things you can do help prevent your baby from getting dehydrated.

  • Give your baby more fluids.

    Breastfeed your baby more often. Offer each breast to your baby for 1 to 2 minutes every 10 minutes. If you use a bottle to feed your baby, increase the number of feedings to make up for lost fluids. The amount of extra fluid your baby needs depends on your baby's age and size. For example, a newborn may need as little as 1 fl oz (30 mL) at each extra feeding. A 12-month-old baby may need as much as 3 fl oz (90 mL) at each extra feeding.

  • Check with your doctor about using an oral rehydration solution (ORS).

    If your baby still isn't getting enough fluids from formula or the breast, you can try an ORS, such as Pedialyte. The amount of ORS your baby needs depends on your baby's age and size. You can give the ORS in a dropper, a spoon, or a bottle.

  • Give your baby more cereal.

    If your baby has started eating cereal, you may replace lost fluids with cereal. You also may feed your baby strained bananas and mashed potatoes if your child has had these foods before.

When to call for help during self-care

Call a doctor if any of the following occur during self-care at home:

  • More severe dehydration.
  • Decreased alertness.
  • New or worse dizziness or lightheadedness.
  • Decreased urination.
  • Symptoms occur more often or are more severe.

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Credits

Current as of: July 31, 2024

Author: Ignite Healthwise, LLC Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

Current as of: July 31, 2024

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.