Dehydration
Dehydration occurs when your body does not have as much water and fluids as it should.
Dehydration can be mild, moderate, or severe, based on how much of your body's fluid is lost or not replaced. Severe dehydration is a life-threatening emergency.
Causes
You can become dehydrated if you lose too much fluid, do not drink enough water or fluids, or both.
Your body may lose a lot of fluid from:
- Sweating too much, for example, from exercising in hot weather
- Fever
-
Vomiting
or
diarrhea
Vomiting
Nausea is feeling an urge to vomit. It is often called "being sick to your stomach. "Vomiting or throwing-up is forcing the contents of the stomach ...
-
Urinating too much
(uncontrolled diabetes or some medications, like diuretics, can cause you to urinate a lot)
Urinating too much
Excessive amount of urination means that your body makes larger than normal amounts of urine each day.
You might not drink enough fluids because:
- You do not feel like eating or drinking because you are sick
- You are nauseated
-
You have a
sore throat
or
mouth sores
Sore throat
Pharyngitis, or sore throat, is discomfort, pain, or scratchiness in the throat. It often makes it painful to swallow.
Mouth sores
Trench mouth is an infection that causes swelling (inflammation) and ulcers in the gums (gingivae). The term trench mouth comes from World War I, wh...
Older adults and people with certain diseases, such as diabetes, are also at higher risk for dehydration.
Symptoms
Signs of mild to moderate dehydration:
- Thirst
- Dry or sticky mouth
- Not urinating much
- Darker yellow urine
- Dry, cool skin
- Headache
- Muscle cramps
Signs of severe dehydration:
- Not urinating, or very dark yellow or amber-colored urine
- Dry, shriveled skin
- Irritability or confusion
- Dizziness or light-headedness
- Rapid heartbeat
- Rapid breathing
- Sunken eyes
- Listlessness
- Shock (not enough blood flow through the body)
- Unconsciousness or delirium
Exams and Tests
Your health care provider will look for these signs of dehydration:
-
Low blood pressure
Low blood pressure
Low blood pressure occurs when blood pressure is much lower than normal. This means the heart, brain, and other parts of the body do not get enough ...
- Blood pressure that drops when you stand up after lying down
-
White finger tips that do not return to a pink color
after your doctor presses the fingertip
After your doctor presses the fingertip
The capillary nail refill test is a quick test done on the nail beds. It is used to monitor dehydration and the amount of blood flow to tissue....
-
Skin that is not as elastic as normal
. When the provider pinches it into a fold, it may slowly sag back into place. Normally, skin springs back right away.
Skin that is not as elastic as normal
Skin turgor is the skin's elasticity. It is the ability of skin to change shape and return to normal.
-
Rapid heart rate
Rapid heart rate
A bounding pulse is a strong throbbing felt over one of the arteries in the body. It is due to a forceful heartbeat.
Your doctor may do lab tests:
-
Blood tests to check
kidney function
Kidney function
The creatinine blood test measures the level of creatinine in the blood. This test is done to see how well your kidneys are working. Creatinine can ...
-
Urine tests
to see what may be causing dehydration
Urine tests
Urine specific gravity is a laboratory test that shows the concentration of all chemical particles in the urine.
-
Other tests to see what may be causing dehydration (
blood sugar test for diabetes
)
Blood sugar test for diabetes
Diabetes is a chronic disease in which the body cannot regulate the amount of sugar in the blood.
Treatment
To treat dehydration:
- Try sipping water or sucking on ice cubes.
- Try drinking water or sports drinks that contain electrolytes.
- Do not take salt tablets. They can cause serious complications.
-
Ask your provider
what you should eat if you have diarrhea
.
What you should eat if you have diarrhe
Diarrhea - self-care; Diarrhea - gastroenteritis
For more severe dehydration or heat emergency , you may need to stay in a hospital and receive fluid through a vein (IV). The provider will also treat the cause of the dehydration.
Heat emergency
Heat emergencies or illnesses are caused by exposure to extreme heat and sun. Heat illnesses can be prevented by being careful in hot, humid weather...
Receive fluid through a vein
Intravenous means "within a vein. " Most often it refers to giving medicines or fluids through a needle or tube inserted into a vein. This allows th...
Dehydration caused by a stomach virus should get better on its own after a few days.
Stomach virus
Viral gastroenteritis is present when a virus causes an infection of the stomach and intestine. The infection can lead to diarrhea and vomiting. It...
Outlook (Prognosis)
If you notice signs of dehydration and treat it quickly, you should recover completely.
Possible Complications
Untreated severe dehydration may cause:
- Death
- Permanent brain damage
-
Seizures
Seizures
A seizure is the physical findings or changes in behavior that occur after an episode of abnormal electrical activity in the brain. The term "seizure...
When to Contact a Medical Professional
You should call 911 if:
- The person loses consciousness at any time.
- There is any other change in the person's alertness (for example, confusion or seizures).
- The person has a fever over 102°F (38.8°C).
- You notice symptoms of heatstroke (such as rapid pulse or rapid breathing).
- The person's condition does not improve or gets worse despite treatment.
Prevention
To prevent dehydration:
- Drink plenty of fluids every day, even when you are well. Drink more when the weather is hot or you are exercising.
- If anyone in your family is ill, pay attention to how much they are able to drink. Pay close attention to children and older adults.
- Anyone with a fever, vomiting, or diarrhea should drink plenty of fluids. DO NOT wait for signs of dehydration.
- If you think you or someone in your family may become dehydrated, call your provider. Do this before the person becomes dehydrated.
References
Kenefick RW, Cheuvront SN, O'Brien KK. Dehydration, rehydration, and hyperhydration. In: Auerbach PS. Wilderness Medicine . 6th ed. Philadelphia, PA: Elsevier Mosby; 2012:chap 70.
Padlipsky P. Infectious diarrheal disease and dehydration. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ed. Philadelphia, PA: Elsevier Mosby; 2014:chap 173.
-
Skin turgor - illustration
A decrease in skin turgor is indicated when the skin (on the back of the hand for an adult or on the abdomen for a child) is pulled up for a few seconds and does not return to its original state. A decrease in skin turgor is a late sign of dehydration.
Skin turgor
illustration
-
Skin turgor - illustration
A decrease in skin turgor is indicated when the skin (on the back of the hand for an adult or on the abdomen for a child) is pulled up for a few seconds and does not return to its original state. A decrease in skin turgor is a late sign of dehydration.
Skin turgor
illustration
Review Date: 8/29/2015
Reviewed By: Laura J. Martin, MD, MPH, ABIM Board Certified in Internal Medicine and Hospice and Palliative Medicine, Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.