URL of this page: https://medlineplus.gov/dehydration.html

Dehydration

Summary

When you're dehydrated, your body doesn't have enough fluid and electrolytes to work properly. An average person on an average day needs about 3 quarts of water. But if you're out in the hot sun or are exercising a lot, you need a lot more than that. You can also become dehydrated if you are vomiting, have diarrhea, or are sweating a lot. People who are elderly, very young, taking certain medications, or have a chronic illness have a greater risk.

Signs of dehydration in adults include

  • Being thirsty
  • Urinating less often than usual
  • Dark-colored urine
  • Dry skin
  • Feeling tired
  • Dizziness and fainting

Signs of dehydration in babies and young children include a dry mouth and tongue, crying without tears, no wet diapers for 3 hours or more, a high fever and being unusually sleepy or drowsy.

If you think you're dehydrated, drink small amounts of water over a period of time. Drinking too much all at once can overload your stomach and make you throw up. If you are exercising in the heat and losing a lot of minerals in sweat, sports drinks can be helpful. Avoid any drinks that have caffeine.

NIH: National Institutes of Health

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