Dehydration occurs when the body uses or loses more fluid than it takes in. Then the body doesn’t have enough water and other fluids to do its usual work. Not replacing lost fluids leads to dehydration.
Anyone can become dehydrated. But the condition is more serious for infants, children and older adults.
The most common cause of dehydration in young children is diarrhea and vomiting. Older adults have a lower volume of water in their bodies to begin with. And older adults might have conditions or take medicines, such as water pills, that increase the risk of dehydration.
Dehydration also can occur in anyone who doesn’t drink enough water during hot weather. It’s more likely in people who are active in the heat.
Drinking more fluids usually fixes mild to moderate dehydration. But severe dehydration needs medical treatment right away.
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