Dehydration, or the lack of enough water in the body, can be mild, moderate or severe. The condition is most common in children and adults over 60, according to the University of Maryland Medical Center, or UMMC. Young children are particularly susceptible because they can lose significant amounts of salt and fluids through sweat, vomiting and diarrhea when ill, and fail to drink enough to replace them, explains the Nemours Foundation. Severe dehydration is potentially life-threatening in children, especially babies.
Urinary Signs
Less frequent urination is a primary indication of dehydration. In newborns, more than three hours without a wet diaper is a sign, according to UMMC. In older babies and toddlers, six to eight hours without urination indicates dehydration. Older children and teens may be dehydrated if they don't urinate for eight to 12 hours. In addition, concentrated urine--identifiable by its dark yellow or amber coloration and abnormally strong scent--is a symptom of dehydration in children.
Signs of Bodily Dryness
Dehydration often manifests indications of bodily dryness in children. Increased or extreme thirst, a parched or sticky mouth and dry mucous membranes are all signs, states the Mayo Clinic. Few or no tears while crying, a lack of sweat and dry skin are other signs.
Other Physical Symptoms
A baby's hands and feet may become cold to the touch and may look splotchy when dehydrated, notes Baby Center. Skin elsewhere may also become cool and can lose its elasticity. A child's eyes, abdomen or cheeks may appear sunken as well, says UMMC. Muscle weakness, headaches, high fever, an accelerated heartbeat and rate of breathing, raised blood pressure and dizziness or a lightheaded sensation also indicate dehydration, usually severe, according to the Mayo Clinic. In infants, the fontanels, or soft spots on a baby's head, may also appear sunken. In the most severe cases, a child may become unconscious.
Mood Changes
Dehydration, especially once it becomes serious, can cause notable mood changes in children. Irritability or fussiness, lethargy, fatigue and sleepiness may be seen. Confusion or delirium are signs of extremely severe dehydration.
