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 include:
Signs of severe dehydration include:
To treat dehydration:
For more severe dehydration or heat emergency, you may need to stay in a hospital and receive fluid through a vein (IV). The provider will also treat the cause of the 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:
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.