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Dehydration in Adults

Dehydration in Adults Overview

Dehydration is a condition that occurs when the loss of body fluids, mostly water, exceeds the amount that is taken in. With dehydration, more water is moving out of our cells and then out of our bodies than the amount of water we take in through drinking.

We lose water every day in the form of water vapor in the breath we exhale and as water in our sweat, urine, and stool. Along with the water, small amounts of salts are also lost.

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When we lose too much water, our bodies may become out of balance or dehydrated. Severe dehydration can lead to death.

Causes of Dehydration in Adults

Many conditions may cause rapid and continued fluid losses and lead to dehydration:

  • Fever, heat exposure, and too much exercise
  • Vomiting, diarrhea, and increased urination due to infection
  • Diseases such as diabetes
  • The inability to seek appropriate water and food (as in the case of an infant or disabled person)
  • An impaired ability to drink (for instance someone in a coma or on a respirator or a sick infant who cannot suck on a bottle)
  • No access to safe drinking water
  • Significant injuries to skin, such as burns or mouth sores, or severe skin diseases or infections (water is lost through the damaged skin)

Symptoms of Dehydration in Adults

The signs and symptoms of dehydration range from minor to severe and include:

  • Increased thirst
  • Dry mouth and swollen tongue
  • Weakness
  • Dizziness
  • Palpitations (feeling that the heart is jumping or pounding)
  • Confusion
  • Sluggishness fainting
  • Fainting
  • Inability to sweat
  • Decreased urine output

Urine color may indicate dehydration. If urine is concentrated and deeply yellow or amber, you may be dehydrated.

When to Seek Medical Care

Call your doctor if the dehydrated person experiences any of the following:

  • Increased or constant vomiting for more than a day
  • Fever over 101°F
  • Diarrhea for more than 2 days
  • Weight loss
  • Decreased urine production
  • Confusion
  • Weakness

Take the person to the hospital's emergency department if these situations occur:

  • Fever higher than 103°F
  • Confusion
  • Sluggishness (lethargy)
  • Headache
  • Seizures
  • Difficulty breathing
  • Chest or abdominal pains
  • Fainting
  • No urine in the last 12 hours

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