A prolonged bout of diarrhea or vomiting can cause the body to lose more fluid than it can take in. The result is dehydration, which occurs when your body doesn’t have the fluid it needs to function properly. Severe dehydration can cause your kidneys to shut down. Dehydration can be particularly dangerous in children and the elderly.
Know the Signs of Dehydration
- less frequent urination than normal
- dark-colored urine
- dry skin
- inability to sweat
By the time these symptoms show up, however, dehydration may be well advanced. At the first sign of diarrhea or vomiting, begin replacing lost water and the essential salts called electrolytes.
How to Prevent Dehydration
When you’re sick with diarrhea or vomiting, you lose fluid rapidly. So it’s important to take in as much fluid as you can. Drinking plenty of water is the top priority. The amount of water you need to replenish depends on how much is being lost.
People with certain medical conditions such as heart failure or incontinence may need to limit their fluid intake, so ask your doctor how much fluid you need to prevent dehydration when you’re sick.
If you’re nauseated, keeping fluids down may be difficult. “Try sipping small amounts of water as frequently as possible,” advises Joshua Evans, MD, a physician at Children’s Hospital of Michigan in Detroit and an expert on dehydration. Sucking on ice or frozen Popsicles can help increase fluid intake.
Water rehydrates the body. “But water alone doesn’t replace the essential salts required by the body for fluid balance and other functions,” Evans says. Replacing these essential salts is crucial during a bout of diarrhea or vomiting. Most experts recommend drinking oral rehydration solutions.
Dehydration experts also recommend remove excess clothing and/or seeking shade or an air-conditioned shelter to keep your body cool.
Preventing Dehydration in Children
Children can lose a tremendous amount of fluid in a short time from diarrhea or vomiting. In addition to routine signs of dehydration, parents of sick infants and children should also watch for dry mouth and tongue, no tears when crying, listlessness or crankiness, sunken cheeks or eyes, sunken fontanel (the soft spot on the top of a baby's head), fever, and skin that does not return to normal when pinched and released. Call your doctor if you notice any of these symptoms in your child.
If your sick child shows signs of dehydration, give fluids called oral rehydration solutions. Sports drinks and fruit juices are helpful too, but they don’t provide the ideal balance of water, sugar, and salt. Instead, pediatricians recommend oral rehydration solutions such as Ceralyte, Infalyte, or Pedialyte. If your child is not vomiting, these fluids can be used in very generous amounts until your child starts making normal amounts of urine again. If your child is dehydrated and vomiting, call your doctor.
Preventing Dehydration in the Elderly
Seniors are at increased risk of becoming dehydrated because they may not be as sensitive as younger adults to the sensation of thirst. In addition, age-related changes in the body’s ability to balance water and sodium increase the danger.
An elderly person sick with diarrhea and/or vomiting should try to drink at least 1.7 liters of fluid every 24 hours, or a little less than half a gallon. That’s the equivalent of about 7 eight-ounce glasses of water. Dehydration experts also recommend liquid meal replacements.
When to Get Help for Dehydration
Experts recommend calling your physician if diarrhea or vomiting persists for more than two days. Call sooner if there’s a fever or pain in the abdomen or rectum, if stool appears black or tarry, if signs of dehydration appear. “In general, if you or your child has diarrhea, it’s not improving and you’re worried, I’d say call your doctor,” Evans says.