It can be a little tricky if a stomach bug comes with cramping right before a child has diarrhea.

Story highlights

The two main culprits are the rotavirus and the adenovirus and echovirus

A stomach bug is not a serious illness and will resolve on its own

Call your doctor if there is any blood in the diarrhea or vomit  — 

Uh oh: puke alert!

What parents need to know about treating stomach bugs, keeping your child comfortable, and how long the virus usually lasts

What is the stomach flu?

The “stomach flu” is really a misnomer, explains Barbara Frankowski, MD, professor of pediatrics at Vermont Children’s Hospital in Burlington. “It’s not the flu that you get protection from when you get the flu shot,” says Frankowski. She prefers to use the term stomach bug to describe a group of viruses that can upset your stomach, bringing on nausea, vomiting, and diarrhea.

The two main culprits are the rotavirus, which is more common in the winter months, and the adenovirus and echovirus, both of which prefer the climate in the summer and spring. In fact, says Frankowski, the reason kids seem to get what people call the “stomach flu” so often, is because there are so many viruses that can cause it. The good news is that, while uncomfortable (and, let’s face it, gross), in most kids, a stomach bug is not a serious illness and will resolve on its own after a few days of TLC. Here’s our guide to spotting the symptoms, taking care of your little patient, knowing when to call your doctor, and avoiding it altogether.

How do I know I know it’s stomach flu vs. food poisoning?

Stomach bugs can have a variety of symptoms, says Frankowski. “Some kids will just have a stomachache and a decreased appetite, some will have just vomiting or diarrhea, and some will have the wonderful combination of both.” Your child may have a fever, and, generally speaking, the more symptoms she racks up, the more severe the illness will be. She might also just vomit once, and be done with it.

While food poisoning shares some of those same symptoms, it usually hits pretty quickly after eating the food in question (did Chloe have potato salad at that afternoon’s picnic? Did Ben scarf down the rest of the tuna sandwich that had been sitting on the counter for a few hours?). Though it may come with fever, it often doesn’t, and it usually goes away pretty quickly. Whereas stomach bugs like to hang around for three to five (sometimes even seven) days.

Could it be something worse?

One condition no parent or pediatrician wants to miss is appendicitis, which features a pretty bad stomachache and can involve vomiting too. Here are some ways to distinguish it from other conditions that target the tummy.

Kids with appendicitis will often:

-Have pain around the belly button that moves to the lower right side
-Have a fever
-Not want to eat
-Develop pain that is so severe they refuse to walk, jump, or even move

It can be a little tricky if a stomach bug comes with cramping right before a child has diarrhea, but if the diarrhea relieves it a little that’s a sign it might just be a bug. “If you’re thinking that it’s not just bad vomiting and diarrhea, but your child is really complaining of pain, that’s a good reason to call your doctor and see if they want to check your child out,” says Frankowski. The best thermometers for kids

When should I call a doctor?

“If you have a baby under a year of age, you should be checking with your doctor for anything that goes on for more than two days,” says Frankowski. The main concern with a stomach bug is that nausea and vomiting can lead to dehydration, which can strike little kids much faster, with more serious consequences. According to the Centers for Disease Control and Prevention, 1 in 40 babies who come down with a stomach bug will require hospitalization for dehydration. (see “How do I know if my child is becoming dehydrated?”)

Also call your doctor if there is any blood in the diarrhea or vomit, which is not common with stomach bugs. “You usually see blood in the stool or vomit with more serious bacterial infections such as E. coli,” says Frankowski. “If you see blood, all bets are off. Talk with your doctor right away.”

Other reasons to check in with your pediatrician include any illness that lasts longer than two days for a kid under two, or three days for older kids who don’t show any improvement. How high the fever goes is not as much of a concern to your doctor, says Frankowski, as long as it comes down. If it’s still high after three days for an older kid or two days for kids under two, call your ped. You should also call if your child appears dehydrated (see “How do I know if my child is becoming dehydrated?”) or is not drinking enough fluids (see “Your hydration action plan”) Is the flu shot safe?

What can I do for my kid?

“The best thing is to keep them home,” says Frankowski. “You don’t want to send a kid who is throwing up or having diarrhea to school.”

You can offer them ibuprofen or acetaminophen to help bring a fever down or lessen the pain. It’s fine if your child doesn’t feel up to eating, but he needs to be taking in liquid regularly. So your mission is to keep him hydrated.

How do I keep them hydrated?

Frankowski says to pick any clear fluid—water, juices (try watering them down), ginger ale that has gone flat (leave it on the counter with the cap off for a little while or shake the bubbles out), broth, or electrolyte solutions such as Pedialyte. Frankowski says to steer clear of colas or anything with caffeine, which increases urination and can speed dehydration.

For children under a year, your doctor will probably suggest using an oral rehydration solution such as Pedialyte or Ricelyte, which come in several flavors and even in popsicle form. If your child won’t go for the electrolyte drink, just continue giving small amounts of formula and breast milk more frequently.

To help kids keep liquids down, small, frequent amounts are better than drinking a whole glass. Frankowski advises her patients to try a half-ounce to an ounce (for reference, there are 8 ounces in one cup) every 20 or 30 minutes for kids under two, and the same amount but every 15 to 20 minutes for children older than that. Is it okay to take a sick kid to a walk-in clinic?

How do I know if my child is becoming dehydrated?

The first thing any doctor will want to know is how much liquid is moving through the system. For young kids, “doctors always ask how many wet diapers your kid is making,” says Frankowski. So keep count. For older kids who go to the bathroom on their own, try to keep track of how often they go and listen in to gauge output. If not much is coming out, that’s your first sign that your child is becoming dehydrated.

Other signs of serious dehydration include a mouth that is not moist on the inside. When saliva production stops, “the mucous membranes of the mouth start to feel tacky,” says Frankowski. Another giveaway is if your child is crying but not making tears. “I always feel good when I walk into the exam room and the kid starts crying right away with big tears coming down,” says Frankowski, “I think to myself, ‘Oh good, the kid’s not dehydrated.’”

If your child is showing any signs of dehydration, get your doctor’s office on the phone right away.

Should I be feeding my child?

If your child is in the throws of a bad stomach bug, food is going to be the last thing she wants. But when the storm breaks and she starts to get a little of her appetite back, start slow.

“As soon as they are feeling a little bit hungry, you can advance to the BRAT diet,” advises Frankowski. That stands for bananas, rice, applesauce, or toast. Plain crackers are fine too. Try one item and give it a little time to see how her system handles it. If it comes right back up or out, it’s too soon to go solid.

Are tummy-soothing teas ok? What about probiotics?

“I get a little nervous about the herbal teas,” says Frankowski. “Some of them have pretty potent herbal ingredients that are not meant for kids,” she warns. Frankowski has even seen teas to help congestion that have the strong medication ephedrine in them. So, don’t assume just because it came from the health food store and has pictures of flowers on the box, that it’s safe for your kid. If you’re a big believer in tea, Frankowski recommends trying a weak brew of chamomile, but advises that it should not be your only form of hydration. Or, if you picked something up that you’d really like to try, check with your doctor first. This goes for any age child, but especially those under 12.

As for other supplements such as vitamin D (promoted as an immune system booster) or probiotics, Frankowski says they haven’t been shown to prevent or treat the stomach flu. However, if your child has had really bad diarrhea and his appetite has returned, you can try yogurt with active cultures to help repopulate the good bacteria that normally live in his gut.

How do I keep the rest of the family from getting it?

Stomach bugs are contagious little suckers and they can be spread pretty much the whole time your child is having diarrhea or vomiting (and even up to 24 hours after it has stopped).

They originally get into circulation from fecal matter but can then be spread through saliva and indirect contact (your sick kid touches a doorknob and then you touch it, for instance). So, it’s hard to keep the family healthy. Regular and vigorous hand washing is a must, especially after diaper changes and potty trips. You should also be washing toys as often as you can, especially if your kids are sharing them. Infected toys are one of the reasons stomach bugs spread like wildfire through daycares, where every Tom, Dick and Sally is putting them in their mouth.

When can my child return to school?

“Your child shouldn’t have a fever and should be feeling pretty good,” says Frankowski. “If your kid is throwing up and having diarrhea at night, but feels a little better in the morning, it’s a judgment call on whether you want to chance it,” says Frankowski. If you can, err on the side of caution. The last thing a kid wants is the embarrassment of tossing his cookies in school, and you don’t want to risk your child being the typhoid Mary of her kindergarten. In general, you want your child to “pretty much be back to baseline as far as appetite and being able to keep down food.”

Is there any way to prevent stomach bugs?

As we mentioned, they are social little bugs that like to touch as many people as possible, but good hand hygiene is your best defense. You can’t stop two year-olds from putting everything they see in their mouths, but you can do your best to keep their environment clean and instill good hand washing practices in them.

Everyone in the family should wash hands before meals and after going to the bathroom. When you’re out in public, keep an eye out for germy spots your kids might like to sample. For instance that unexplainably appetizing handle on the grocery cart that your three year old sucks on the minute you put him in. Pack along sanitizing wipes or look for ones in the grocery store and wipe the handles down before you stick him in the seat. Always have hand sanitizer on hand and use it when there’s no sink nearby (it’s especially handy on public transportation).

But, unfortunately, says Frankowski, “Even doing all that is not a one hundred percent guarantee you’ll avoid the stomach bug.”

Can the flu shot or vaccines keep my kids from getting a stomach bug?

As we mentioned before, the “stomach flu” is not actually caused by influenza viruses, which is what the annual flu shot can protect you from. So, even though you and your children should be vaccinated for the flu, it won’t protect you from the family of bugs that can make you sick to your stomach.

In fact, the only stomach bug vaccine that exists is for the rotavirus, and it is only available to children under 6 months of age. “Under one year of age, rotavirus is the most common thing that makes kids so dehydrated they end up in the ER or admitted to a hospital,” says Frankowski. It is a series of two or three oral vaccines that are not part of the regular vaccination schedule, so Frankowski recommends talking to your pediatrician about it, especially if you are having a winter baby or are planning to put your child in daycare before 6 months.