Your child is throwing up everything they eat, has frequent diarrhea, and has no energy. Stomach flu is uncomfortable for the child and stressful for parents. The good news: most children recover within a few days.
Stomach flu (gastroenteritis) is inflammation of the gastrointestinal tract, usually caused by a virus. The condition is very common in children and spreads quickly in daycare settings and families. The most important thing you can do as a parent is ensure your child gets enough fluids.
Symptoms of Stomach Flu
Stomach flu often comes on suddenly. One moment the child seems fine, the next they're vomiting.
Typical symptoms:
- Vomiting — often the first sign, can come suddenly
- Diarrhea — loose, watery stool, many times per day
- Stomach pain and cramps
- Decreased appetite
- Fever (not always)
- Fatigue and general malaise
Vomiting typically lasts 1-2 days, while diarrhea can persist for 5-7 days. In some children, loose stool can last up to 2 weeks.
Norovirus is the most common cause of stomach flu in children. Rotavirus was previously the biggest culprit in infants, but after the rotavirus vaccine was introduced in childhood vaccination programs, the incidence has dropped significantly.
Hydration: The Most Important Treatment
The main goal with stomach flu is to prevent and treat fluid loss. Children dehydrate faster than adults, and the younger the child, the more vulnerable they are.
For Breastfed Infants
Continue breastfeeding — more frequently than usual, with shorter sessions. Breast milk is easily digestible and contains important nutrients and antibodies that help the child recover.
If the child vomits after feeding, wait 15-20 minutes and try again with a shorter session.
For Formula-Fed Infants
Continue with formula as usual. Give smaller amounts more frequently. Don't water down the formula — the mixing ratio should stay the same.
For Older Babies and Toddlers
- Give small sips of fluid often — every 5-10 minutes
- Oral rehydration solution (ORS) from the pharmacy is the gold standard. It replaces salt and sugar lost through vomiting and diarrhea. Mix according to package instructions.
- Water, diluted juice, broth, and ice chips can also be used
- Avoid sugary drinks like soda and undiluted juice — high sugar content can worsen diarrhea
Child refusing to drink? Try giving fluid with a teaspoon or syringe (without needle). A teaspoon every 2-5 minutes is better than nothing. Popsicles or frozen fruit juice cubes can tempt children who won't drink.
Hydration Checklist
- Give fluids in small portions, not large amounts at once
- After vomiting: wait 15-30 minutes, start with a teaspoon, increase gradually
- Use ORS from the pharmacy if the child vomits repeatedly or has heavy diarrhea
- Count wet diapers — the child should have at least 4-6 wet diapers in 24 hours
Food During Stomach Flu
Have you heard that children should fast during stomach flu? That's not true. Research shows that children who start eating again early recover faster.
When the child starts to manage food:
- Start with easily digestible food: bread, crackers, rice, pasta, potato, banana
- Avoid fatty and heavily spiced food the first days
- Give small portions, but offer food often
- Don't force the child to eat — appetite will return on its own
For infants who have started solids: begin with simple foods like porridge, potato mash, or banana mash. Scale back to simpler foods than what the child usually eats.
Signs of Dehydration
Dehydration is the most serious complication of stomach flu. Learn to recognize the signs, as it requires quick action.
Mild signs (contact doctor):
- Drier mouth than usual
- Fewer wet diapers (under 4 in 24 hours)
- Child cries with fewer or no tears
- Darker urine than usual
- Child is more listless and tired than expected
Serious signs (contact doctor immediately):
- No wet diaper for 6-8 hours
- Sunken eyes
- Sunken fontanelle (the soft spot on the head in infants)
- Child is very lethargic or difficult to wake
- Dry, cracked lips and mouth
- Skin folds when you gently pinch it (decreased skin turgor)
Contact a doctor quickly if the child can't keep fluids down, shows signs of dehydration, has blood in the stool, or has a high fever. For infants under 6 months with stomach flu, always contact a doctor early — they dehydrate fastest.
When Should You Contact a Doctor?
Contact your pediatrician or urgent care for:
- Child is under 6 months
- Signs of dehydration (see list above)
- Vomiting lasting more than 24 hours in infants, or 48 hours in older children
- Blood in vomit or stool
- High fever (over 102.2°F in infants, over 104°F in older children)
- Severe stomach pain that doesn't subside
- Child is very listless and barely responsive
- Diarrhea lasting more than 7 days
Call emergency services (911) for:
- Child is unconscious or very difficult to wake
- Child is having seizures
- Severe signs of dehydration not responding to fluid intake
Infection Control and the 48-Hour Rule
Stomach flu is highly contagious. The virus spreads through direct contact, vomit, and stool, and can survive on surfaces for several days.
The 48-Hour Rule
The child should stay home from daycare for at least 48 hours after the last episode of vomiting or diarrhea. This rule also applies to adults in the household who become ill.
How to Limit Spread in the Family
- Wash hands thoroughly with soap and water after diaper changes, after vomiting, and before food preparation
- Hand sanitizer alone is not enough against norovirus — soap and water are more effective
- Clean surfaces the child has been in contact with (changing table, toys, door handles)
- Use separate towels for the sick child
- Wash bedding and clothes at high temperatures
- Try to keep the sick child away from other children in the family
Have a "sick kit" ready with a vomit bucket, towels, dry shampoo, ORS powder from the pharmacy, and extra bedding. Then you're prepared next time stomach flu strikes.
Prevention
- Hand hygiene is the most important — teach your child to wash hands with soap
- Rotavirus vaccine is given to infants as part of recommended childhood vaccinations
- Food hygiene — wash fruits and vegetables, keep raw and prepared food separate
- Keep sick children home from daycare until symptom-free for 48 hours
Frequently Asked Questions
Can the child drink milk during stomach flu?
Breast milk and formula can and should be given as usual. For older children, you may want to reduce cow's milk the first few days if diarrhea is severe, as some children may develop temporary lactose intolerance. Talk to your pediatrician if you're unsure.
Should I give my child probiotics?
Some studies show that certain probiotic strains (especially Lactobacillus rhamnosus GG) can shorten the duration of diarrhea by about one day. Talk to your doctor or pharmacist about whether this may be appropriate for your child.
How long is the child contagious?
The child can be contagious from when symptoms start and up to 48 hours after symptoms are gone. With norovirus, the contagious period can last even longer.
Can stomach flu come back right away?
Yes. There are many different virus types that cause stomach flu, and immunity to one type doesn't protect against others. A child can get stomach flu multiple times in a single year.
See also: First Aid for Infants