Dehydration occurs when your body does not have as much water and fluids as it needs.
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.
Vomiting - dehydration; Diarrhea - dehydration; Diabetes - dehydration; Stomach flu - dehydration; Gastroenteritis - dehydration; Excessive sweating - dehydration
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:
You might not drink enough fluids because:
Older adults and people with certain diseases, such as diabetes, are also at higher risk for dehydration.
Signs of mild to moderate dehydration:
Signs of severe dehydration:
Exams and Tests
Your health care provider will look for these signs of dehydration:
Your provider may do lab tests such as:
To treat dehydration:
Dehydration caused by a stomach virus should get better on its own after a few days.
If you notice signs of dehydration and treat it quickly, you should recover completely.
Untreated severe dehydration may cause:
When to Contact a Medical Professional
You should call 911 if:
To prevent dehydration:
Kenefick RW, Cheuvront SN, Leon LR, O'brien KK. Dehydration and rehydration. In: Auerbach PS, Cushing TA, Harris NS, eds. Auerbach's Wilderness Medicine. 7th ed. Philadelphia, PA: Elsevier; 2017:chap 89.
Padlipsky P, McCormick T. Infectious diarrheal disease and dehydration. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 172.
Review Date: 9/5/2017
Reviewed By: Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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