Dehydration is the failure to keep up with loss of water and salt from the body. The most common cause is exposure to very hot or arid (low humidity, such as occurs in desert or winter conditions). Fever can also cause dehydration, as can diarrhea. Dehydration is especially dangerous in the young and elderly.

Early markers of dehydration include thirst, decreased energy and change in urination pattern (typically less frequent, more concentrated urine that is darker in color and may burn with passage). More advanced dehydration may cause dry mouth and tongue, extreme thirst, and little or no urination or sweating. Other signs include weight loss, fast heartbeat, and sunken eyes. Late signs may include dizziness and confusion.


  • Be attentive to hydration, especially prior to and during exertion in hot or low humidity conditions.
  • Be aware of signs and symptoms of dehydration, especially if you are ill with fever or diarrhea.


Home care   Home Care

  • Slowly and steadily drink water, apple juice, coconut water or oral rehydration solution until your thirst is quenched and normal sweating and urination resume.
  • Eat small bites of saltine crackers to replace salt.
  • For vomiting or diarrhea, see sections below.


Professional care   Professional Care

Seek medical attention if:

  • You remain symptomatic for an extended time despite efforts to rehydrate.
  • You are too weak or dizzy to stand up or move around.
  • You have persistent, uncontrollable rapid breathing or heart rate.
  • Your symptoms are otherwise very intrusive or worrisome.