Health Library

Health Library

Dehydration and Rehydration in Children

Dehydration happens when a person loses more fluids than he or she takes in. Human bodies are made up largely of water, so the right balance of fluids in our systems is needed for good health. Large amounts of fluids can be lost through fever, diarrhea, vomiting, or sweating. Dehydration happens very quickly in the bodies of infants and small children, who don’t have as much fluid to spare. It can quickly become very serious. Rehydration is the crucial process of returning those fluids back to the body to restore normal functioning.

Signs of Dehydration

Watch for the following signs of dehydration (especially if your child has a fever, diarrhea, or is vomiting):

• Dry mouth or extreme thirst

• Fewer than 6 wet diapers a day for infants, or no urination for 6 hours in older children

• Fussy or agitated behavior

• Looking or acting very tired or weak

Treating Dehydration

If you suspect dehydration, call your doctor. You can treat mild dehydration at home by doing the following:

• Keep track of your child’s fluid intake and how often he or she urinates.

• Breastfeed or bottle-feed a sick infant more often but for shorter periods of time.

• For vomiting or diarrhea, give the child 2–3 teaspoons of an oral rehydration solution (ORS) such as Pedialyte, Infalyte, or Kaoelectrolyte, every 10 minutes. Continue until the child can drink larger amounts of fluid without vomiting or passing stool.

• Avoid soft drinks, tea, juice, broth, or “sports drinks” like Gatorade. These may make symptoms worse.

• DO NOT give your child dairy products, which can make vomiting and diarrhea worse.

• DO NOT use medications for vomiting and diarrhea unless recommended by your doctor.

If your child has a hard time keeping fluids down and becomes very dehydrated, your doctor may decide to treat him or her in a hospital. In the hospital, the child can be made comfortable and given fluids and nourishment through an intravenous (IV) line. This will continue until he or she can eat and drink again.

Get immediate medical attention if the child:

• Fever:

  • Is an infant under 3 months old, with a rectal temperature of 100.4°F (39.0°C) or higher

  • Is a child 3 to 36 months, with a rectal temperature of 102°F (39°C) or higher

  • Is a child of any age who has a temperature of 103°F (39.4°C) or higher

  • Has a fever that lasts more than 24-hours in a child uner 2 years old, or for 3 days in a child 2 years or older

  • Has had a seizure caused by the fever

• In infants: is vomiting all feeds (not just spitting up).

• Has been vomiting and having diarrhea for more than 12 hours.

• Hasn’t urinated for 6 hours or more, or has dark or strong-smelling urine.

• Can’t drink even small amounts of liquid without vomiting.

• Cannot be soothed or is very irritable or restless

• Seems unusually drowsy, listless, weak, or limp.

• Has muscle cramps.

• Has dry, wrinkled, or pasty-looking skin, sunken-looking eyes, a very dry or sticky mouth, or cracked lips.