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Treating Dehydration in Adults and Children Over 12

Call 911 if the person has:

  • Extreme thirst
  • Dry skin, mouth, and mucous membranes
  • Little or no urination for 12 hours or more
  • Increased heart rate and breathing
  • Lethargy or fatigue
  • Light-headedness, dizziness, or confusion
  • Dehydration due to heat stroke; NOTE: Follow this link to see what to do about heat stroke.

1. Replace Fluids

For mild dehydration or while waiting for medical care for an adult with severe dehydration that is not due to heat stroke:

  • The person should try to drink 2 quarts of fluid, such as water, juice, or sports drinks, in 2 to 4 hours. But it is better to drink small amounts of fluid often, because drinking too much fluid at once can bring on vomiting.
  • The person should drink at least 10 glasses of liquid a day to replace lost fluids.
  • If the person is elderly, fluid replacement may need to be done slowly. Consult a doctor.
  • If the person is vomiting, try ice chips, popsicles, and small sips of fluid.
  • If the person is recovering from diarrhea, consider that some sports drinks contain a lot of sugar, which can worsen diarrhea.

2. When to Call a Doctor for Mild Dehydration

Seek medical help if:

  • The person’s symptoms get worse or don't improve within 24 hours.
  • The person is elderly.
  • You think a prescription medication such as a diuretic caused the dehydration.

3. Follow Up

  • For mild dehydration, the person should rest for 24 hours and keep drinking fluids, even if symptoms improve. Fluid replacement may take up to a day and a half.
  • If dehydration is moderate to severe, fluids may need to be replaced intravenously (IV) in the hospital.

WebMD Medical Reference

Reviewed by Elaine Magee, MPH, RD on October 10, 2013

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