This article was updated on 7/5/24.

It can be hard to tell if your little one’s diarrhea or throw-up is cause for concern. In this article, we’ll guide you through the ups and downs of viral gastroenteritis, also known as the “stomach bug.” Stomach inflammation can stem from an infection, food poisoning, and most commonly–a virus. Learn what you can do at home as a parent to help, including foods to avoid and symptoms to watch out for.

Stomach bug symptoms

Typically, a viral stomach bug begins with vomiting and stomach aches, with diarrhea happening a bit later on. Often, vomiting and diarrhea overlap. There may be fevers at the start as well.

What is diarrhea?

Diarrhea means 3 or more watery stools. Each episode must be at least 10 minutes apart. Know that 1 or 2 loose stools can be common with diet changes, and aren’t usually a cause for concern.

Diarrhea severity can vary.

Mild diarrhea means 3-5 watery stools per day.
Moderate diarrhea means 6-10 watery stools per day.
Severe diarrhea means over 10 watery stools per day.

Severe diarrhea may occur for the first 1-2 days of a stomach bug.

Nausea and vomiting

Vomiting, or throwing up, can be the body's way of protecting the stomach and intestines. An episode of vomiting is the forceful emptying of a large portion of the stomach's contents. Nausea and abdominal discomfort usually happen before vomiting occurs.

It’s important to know how many times your child has vomited in a day. Each episode must be at least 10 minutes apart. It’s also helpful to know over how many hours the vomiting occurred.

Vomiting severity can vary.

Mild vomiting means 1-2 episodes of vomiting per day.
Moderate vomiting means 3-7 episodes of vomiting per day.
Severe vomiting means 8 or more episodes of vomiting in a day OR vomiting everything for over 8 hours.

Moderate vomiting usually stops in 12 to 24 hours.

Occasional vomiting, upset stomach, and mild diarrhea can continue off and on for up to 1 week.

Managing diarrhea and vomiting

The key to treating vomiting and diarrhea is to prevent too much fluid loss. Make sure your child drinks more age-appropriate fluids to stay hydrated. Some children may not tolerate solid foods. That’s okay–liquids are less likely to cause further vomiting. Have them take small amounts of electrolyte fluids for the first 24 hours or so of the illness.

After the first 24 hours, you can reintroduce solid foods. To help heal the stomach, have your child eat bland foods as tolerated, especially for the first 48-72 hours of the stomach bug.

Keep an eye out for a diaper rash. If your child develops redness to their diaper area, use wet paper towels with warm water instead of commercial diaper wipes. Give your child some diaper-free time when possible. You can also use A&D ointment or Aquaphor.

Treating mild dehydration

The main risk of diarrhea and vomiting is dehydration. Dehydration means the body has lost too much fluid.

If you notice your child seems slightly dehydrated, is having less urine output than normal, or is having frequent watery stools (2 or more), you can use oral rehydration solutions (ORS) with electrolytes (like Pedialyte).

For infants, you can give 2-4 ounces (60-120 ml) of ORS after every large watery stool. You should also continue giving breastmilk, formula or cow's milk.

For children over 1 year, you can give 4-8 ounces (120-240 ml) of ORS after every large watery stool.

Signs of dehydration: what to look out for

Make sure your child is urinating at least 4-6 times in 24 hours, or is having at least 4-6 wet diapers in 24 hours. Pay attention to your child’s energy levels as well. If they’re acting “out of it,” or extra tired, and urinating less, they are likely dehydrated.

Signs of dehydration include:

No tears when crying.
Dry mucous membranes (such as dry, sticky mouth or tongue).
Sunken eyes.
Increased fussiness or sleepiness.
Dizziness when trying to stand, for older children.
Urinating only 1 or 2 times in 24 hours.

If your child is having any signs or symptoms of dehydration, call your pediatrician right away. If your child becomes very lethargic or hard to wake, call 911 or take them to the Emergency Department at once.

What can I do if my child is vomiting?

If your child is having mild to moderate vomiting, you can offer small amounts of age-appropriate liquids. Encourage your child to suck or drink small amounts of fluids every few minutes over a few hours. The goal is to have them take at least 1 ounce of fluid per hour.

Older children (age 1 year and up)

Give water, Pedialyte, or half-strength sports drinks (half drink, half water). You can also offer popsicles or ice chips. Older kids can slowly sip fluids.

Infants (children under 1 year)

Give undiluted breast milk, formula, or Pedialyte to infants. Do not use water.

If your child refuses to drink, try offering fluids with a syringe, spoon, or sippy cup–whatever works!

Breastfeeding babies

If your baby is breastfed, you can continue to breastfeed. If they vomit right after nursing, try breastfeeding more frequently for a shorter period of time. For example, breastfeed every 30 minutes for 5 minutes at a time.

Bland diet recommendations

One important but sometimes overlooked way to manage viral gastroenteritis is to eat a bland diet. It can be helpful to adjust your child’s diet for a few days. Below are recommendations of foods to try and foods to avoid on a bland diet.

It’s okay to give formula, breastmilk, and low-fat dairy on a bland diet. Some general guidelines of foods to offer include more starchy grains, vegetables, and lean meats that are not heavily seasoned. Avoid fried, fatty, or rich dishes on a bland diet. Some examples of foods to eat include rice cereals, crackers, pasta, rice with boiled carrots, bananas, and applesauce.

Dairy to try

Low-fat/fat-free milk and dairy products.

Veggies and fruits to try

Cooked vegetables are easier on the stomach than raw veggies.
Some fruit and vegetable juices are OK on a bland diet. (Some people, especially those with GERD, may want to avoid citrus.)

Starches to try

Breads, crackers, and pasta made with refined white flour.
Refined, hot cereals, such as Cream of Wheat (Farina cereal).

Meats and proteins to try

Lean, tender meats, such as chicken, whitefish, and shellfish.
Creamy peanut butter.
Eggs.
Tofu.

Other foods and drinks to try

Pudding and custard.
Soup, especially broth.
Weak tea.

Foods and drinks to avoid on a bland diet

Avoid apple juice and prune juice, as these can make diarrhea worse.
Avoid fatty dairy, like whipped cream or high-fat ice cream.
Avoid vegetables that make you gassy (such as broccoli, cabbage, cauliflower, green peppers, and corn).
Avoid seedy fruits such as berries or figs, and avoid dried fruit.
Avoid whole-grain bread, crackers, cereal, or pasta.
Avoid highly seasoned foods, including hot pepper or garlic spices, and foods with lots of sugar.

Try to follow a bland diet until your child’s stomach feels better. It is important not to restart regular food right away. Readjusting the gut microbiome can take some time after a GI virus.

When to see a doctor

If your child is not urinating at least every 6 hours, is vomiting for more than 3 days, or has diarrhea for more than 5 days, give your pediatrician's office a call.

Call your pediatrician if your child has:

Severe diarrhea, or blood or mucus in their stool.
Abdominal pain.
Fever, especially with abdominal pain.
Severe vomiting, or is unable to keep any feeds down.
Signs of dehydration.

Once your child’s fevers have resolved for 24 hours with no medication and they are no longer vomiting, they are able to return to school or daycare.

Resources:

This article was written by Katie Taibl, BSN, RN, CPN. Katie is the Patient and Family Outreach Educator at Roslindale Pediatric Associates. She was previously a Pediatric Float Pool RN at Tufts Children’s Hospital, where she worked in Pediatric Med-Surg, PICU, NICU, and Oncology. As a former travel nurse, she was contracted at multiple children’s hospitals, including Boston Children’s Hospital. She is passionate about writing articles on relevant pediatric health topics to help patients and families access actionable, user-friendly health content.