Proceeds from website advertising help sustain Lab Tests Online. AACC is a not-for-profit organization and does not endorse non-AACC products and services.


Print this article
Share this page:

Signs and Symptoms

Signs and symptoms of dehydration will vary with duration of reduced fluid intake and from person to person.

Early dehydration has no symptoms. Mild to moderate dehydration may cause few to no noticeable symptoms, but individuals may experience symptoms that include:

  • Increased thirst
  • Dry and/or sticky mouth
  • Less frequent urination, and urine may be darker yellow, indicating concentration
  • Constipation
  • A decrease in tears
  • Mildly sunken eyes in an infant
  • Fatigue
  • Dry skin
  • Headache
  • Feeling lightheaded or dizzy

Severe dehydration can cause increasingly serious signs and symptoms, such as:

  • Lack of tears and sweating
  • Lack of urine – little to no urine produced and dark yellow in color
  • Intense thirst
  • Extremely dry mouth and mucous membranes
  • Dry skin that lacks elasticity
  • Sunken eyes in an infant
  • Sunken fontanelles in an infant (the soft spots on top of the head)
  • Rapid breathing
  • Increased heart rate
  • Low blood pressure
  • Confusion and, in critical cases, unconsciousness

« Prev | Next »