Dehydration happens when a person loses more fluids than he or she takes in. The human body is made up largely of water, so you need the right balance of fluids in your system for good health. Large amounts of fluids can be lost through fever, diarrhea, vomiting, or sweating. Dehydration happens very quickly in infants and small children. This is because they don’t have as much fluid to spare. Dehydration can quickly become very serious. Rehydration is the important way of returning those fluids back to the body. This restores normal functioning.
Watch for the following signs of dehydration. This is especially true if your child has a fever or diarrhea, or is vomiting:
Dry mouth or extreme thirst
Fewer than 6 wet diapers a day for infants, or less frequent urination in older children
Fussy or agitated behavior
Looking or acting very tired or weak, or increased sleeping
If you suspect dehydration, call your healthcare provider. You can treat mild dehydration at home by doing the following:
Keep track of how much fluid your child drinks 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 your child 1 to 2 teaspoons of an oral rehydration solution (ORS) every 10 minutes. Continue until your child can drink larger amounts of fluid without vomiting or passing stool.
Avoid soft drinks, tea, juice, broth, or sports drinks like electrolyte solutions. These may make symptoms worse.
Do not use medicines for vomiting and diarrhea, unless your healthcare provider tells you to.
If your child has a hard time keeping fluids down and becomes very dehydrated, your healthcare provider may decide to treat him or her in a hospital. There, a healthcare provider can make your child comfortable. Your child will be given fluids and nourishment by mouth or through an intravenous (IV) line. Medicine may be given to stop the vomiting and allow your child to drink enough fluid to stay hydrated.
Get medical care right away if your child:
Has fever (see Fever and children, below)
Is an infant vomiting all feeds (not just spitting up)
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
Always use a digital thermometer to check your child’s temperature. Never use a mercury thermometer.
For infants and toddlers, be sure to use a rectal thermometer correctly. A rectal thermometer may accidentally poke a hole in (perforate) the rectum. It may also pass on germs from the stool. Always follow the product maker’s directions for proper use. If you don’t feel comfortable taking a rectal temperature, use another method. When you talk to your child’s healthcare provider, tell him or her which method you used to take your child’s temperature.
Here are guidelines for fever temperature. Ear temperatures aren’t accurate before 6 months of age. Don’t take an oral temperature until your child is at least 4 years old.
Infant under 3 months old:
Ask your child’s healthcare provider how you should take the temperature.
Rectal or forehead (temporal artery) temperature of 100.4°F (38°C) or higher, or as directed by the provider
Armpit temperature of 99°F (37.2°C) or higher, or as directed by the provider
Child age 3 to 36 months:
Rectal, forehead (temporal artery), or ear temperature of 102°F (38.9°C) or higher, or as directed by the provider
Armpit temperature of 101°F (38.3°C) or higher, or as directed by the provider
Child of any age:
Repeated temperature of 104°F (40°C) or higher, or as directed by the provider
Fever that lasts more than 24 hours in a child under 2 years old. Or a fever that lasts for 3 days in a child 2 years or older.
© 2000-2017 The StayWell Company, LLC. 780 Township Line Road, Yardley, PA 19067. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.