Dr. Catherine Larson-Nath is a M Physicians pediatric gastroenterologist– An expert in researching and caring for the gastrointestinal (GI) tract, liver and pancreas in young patients. 

Her focus is on nutrition and growth in kids who have intestinal failure and others who have illnesses related to their bowels, “and a big part of that can be diarrhea, for many children. So I do a lot in that realm as well.”

Which brings us to what can happen in young patients who develop gastroenteritis. 

What is gastroenteritis?

Catherine Larson-Nath, MD

Gastroenteritis is a common GI illness, according to Dr. Larson-Nath, that many people may refer to as the “stomach flu,” even though it is not related to influenza.

In addition to experiencing diarrhea, both younger and older patients with gastroenteritis may also have symptoms like vomiting or fever. The illness itself usually lasts from four to seven days, but loose stools may last for several weeks.

“It’s very contagious and can just run through households, families, schools and anywhere people are in close contact,” Dr. Larson-Nath explains. 

In young patients, gastroenteritis is most commonly defined as having three loose, watery stools a day, but Dr. Larson-Nath says that for some, three stools a day is normal. “So we say at least two more than the normal number of poops a day that a kid will have is concerning for gastroenteritis.”

It’s most often caused by a virus, like norovirus. Rotavirus can also be a cause, though Dr. Larson-Nath says it’s much less common now thanks to safe and effective vaccines. 

Bacteria, like E. coli, Salmonella, C. diff. or shigella can also be sources, and she adds that if it’s bacterial, you may see blood in the stool, which is less common with viral causes.

Spotting and Preventing Dehydration, and When to Seek Care

The biggest worry Dr. Larson-Nath has when kids are sick is keeping them hydrated. She stresses that dehydration is one of the most important reasons to seek care either from a pediatrician or in the emergency room. 

Keep an eye out for these signs of dehydration when kids are sick: 

  • They can’t keep food down 
  • They have very little or no urination
  • They don’t produce tears when they cry
  • Their mouths are dry

To prevent dehydration, Dr. Larson-Nath says parents or guardians should make sure kids are staying hydrated and that they have options beyond water. 

“Using electrolyte solutions, like Pedialyte or another version you can get at the store, in small amounts frequently can help keep kids hydrated,” she explains.

Maybe Not Just the B.R.A.T.

When it comes to eating, especially if a kid’s appetite has been low, Dr. Larson-Nath says that it’s important to reintroduce foods in a balanced way with proteins, complex carbohydrates and vegetables. Starting with some of their favorites is usually a good way to do it.

“Things like that can help kids get over this,” she explains, adding, “In the past, people really thought it was important to do the B.R.A.T. diet–so bananas, rice, applesauce and toast, but that actually is not needed since it generally doesn’t provide enough calories.”

There’s one thing to avoid though, she cautions: simple sugars like those found in apple juice. The body doesn’t absorb those sugars as easily, and they can even make diarrhea persist longer.

Keeping Gastroenteritis at Bay

“Prevention is a huge key,” explains Dr. Larson-Nath, because the viruses and bacteria that cause gastroenteritis spread through anything someone may touch that comes in contact with their mouth. 

Since it is developmentally common for kids to put things in their mouths, Dr. Larson-Nath says it can be hard to avoid, but good prevention comes down to handwashing with soap and warm water for at least 20 seconds. 

A final note from Dr. Larson-Nath, too. For patients who are immunocompromised, prevention is even more important because their bodies may have a harder time fighting off the disease, and illness could be prolonged. 

“We want people to know that if diarrhea, low appetite or other symptoms persist beyond two weeks for anyone, it would be time to see your pediatrician or family practice provider to make sure this is not more of a long-term or chronic cause.”