Dehydration occurs when you 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 may get dehydrated.
Common causes of dehydration include intense diarrhea, vomiting, fever or excessive sweating. Not drinking enough water during hot weather or exercise also may cause dehydration. Anyone may become dehydrated, but young children, older adults and people with chronic illnesses are most at risk.
You can usually reverse mild to moderate dehydration by drinking more fluids, but severe dehydration needs immediate medical treatment. The safest approach is prevention of dehydration. Monitor your fluid loss during hot weather, illness or exercise, and drink enough liquids to replace what you lose.
Mild to moderate dehydration is likely to cause:
Severe dehydration, a medical emergency, can cause:
Unfortunately, thirst isn't always a reliable gauge of the body's need for water, especially in children and older adults. A better indicator is the color of your urine: Clear or light-colored urine means you're well hydrated, whereas a dark yellow or amber color usually signals dehydration.
When to see a doctor
Get immediate medical care if you develop severe signs and symptoms such as extreme thirst, a lack of urination, shriveled skin, dizziness and confusion.
Treat children and older adults with greater caution. Call your family doctor right away if your loved one:
Go to the nearest hospital emergency room or call 911 or your emergency medical number if you think a child or older adult is severely dehydrated. You can help prevent dehydration from becoming severe by carefully monitoring someone who is sick and giving fluids, such as an oral rehydration solution (Pedialyte, others) at the first sign of diarrhea, vomiting or fever and by encouraging children to drink plenty of water before, during and after exercise.
Dehydration occurs when there isn't enough water to replace what's lost throughout the day. Your system literally dries out. 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:
Anyone can become dehydrated if they lose too many fluids. But certain people are at greater risk, including:
Dehydration can lead to serious complications, including:
Preparing for your appointment
You're likely to start by seeing your, or your child's, doctor. However, in some cases when you call to set up an appointment, the doctor may recommend urgent medical care. If your child or an adult who you care for is showing signs of severe dehydration, such as lethargy or reduced responsiveness, seek immediate care at a hospital.
If you have time to prepare for your appointment, here's some information to help you get ready, and what to expect from the doctor.
What you can do
For dehydration, some basic questions to ask the doctor include:
What to expect from your doctor
What you can do in the meantime
Tests and diagnosis
Your doctor can often diagnose dehydration on the basis of physical signs and signs and symptoms such as little or no urination, sunken eyes, and skin that lacks its normal elasticity and resilience when pinched. If you're dehydrated, you're also likely to have low blood pressure, especially when moving from a lying to a standing position, a faster than normal heart rate and reduced blood flow to your extremities.
To help confirm the diagnosis and pinpoint the degree of dehydration, you may have other tests, such as:
If it's not obvious why you're dehydrated, your doctor may order additional tests to check for diabetes and for liver or kidney problems.
Treatments and drugs
The only effective treatment for dehydration is to replace lost fluids and lost electrolytes. The best approach to dehydration treatment depends on age, the severity of dehydration and its cause.
Treating dehydration in sick children
Treating dehydration in sick adults
Treating dehydration in athletes of all ages
Treating severe dehydration
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. Fluids can be obtained not just from water but also from other beverages and foods. But, if you're exercising, don't wait for thirst to keep up with your fluids.
Under certain circumstances, you may need to take in more fluids than usual:
Last Updated: 2011-01-07
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