Most kids can go back to school or daycare once they have gone at least 24 hours without vomiting, are drinking normally, and feel well enough to join in. If it looks like a stomach bug such as norovirus, waiting 48 hours after the last vomit or diarrhea is safer: that is what the NHS advises, and the CDC tells people with norovirus to wait 48 hours after symptoms stop before caring for others. Your school's written policy has the final say. Green vomit, blood in the vomit, or severe belly pain needs emergency care, not a school plan.
Is the rule 24 hours or 48 hours?
It depends on who you ask, and the difference comes down to how contagious a stomach bug is.
The American Academy of Pediatrics (AAP) says a child should stay home from child care if they have vomited 2 or more times in the past 24 hours, unless the vomiting has a cause that is not an infection and they are not at risk of dehydration. The AAP page does not give a separate return rule, so in practice that means at least 24 hours with no repeat vomiting.
The NHS is stricter. It says to stay off school until there has been no vomiting or diarrhea for at least 2 days. The CDC says people with norovirus should wait at least 48 hours after symptoms stop before handling food or caring for others, and it names schools and daycares as places where this matters. That advice is aimed at people who work in those places, not a school rule for children.
- Threw up once, no other symptoms, fine by morning: many kids can go back the next day if your school allows it
- Vomited 2 or more times in 24 hours: keep them home, per the AAP
- Vomiting plus diarrhea, or others at home or school are sick too: plan on 48 hours after the last episode
- No vomiting, but still not eating, drinking, or able to take part: keep them home a bit longer
Why do stomach bugs get a longer wait?
Norovirus, the leading cause of vomiting and diarrhea in the US, spreads very easily. The CDC says it spreads through direct contact with a sick person, through contaminated food or drinks, and by touching contaminated surfaces and then putting your fingers in your mouth.
Symptoms usually start 12 to 48 hours after exposure, and most people get better in 1 to 3 days. But the CDC says people can still spread it for a few days after they feel better, and the virus can stay in poop for 2 weeks or more after they feel better. The 48-hour wait cuts down the riskiest stretch. It does not make your child zero risk, so handwashing still matters after they go back.
How do I count the hours?
Count from the last time your child vomited or had diarrhea, not from when they started feeling better. If they throw up again, the clock starts over.
Your child should also be keeping fluids down and drinking close to normal before going back. A child who has stopped vomiting but is barely drinking is still at risk of dehydration and is not ready for a full school day.
- Last vomit Monday at 9 pm: 24 hours is Tuesday at 9 pm, so Wednesday morning at the earliest
- Same, but it is a stomach bug and your school uses 48 hours: Wednesday at 9 pm, so Thursday morning
- Diarrhea kept going after the vomiting stopped: count from the last loose stool if your school or the NHS rule applies to diarrhea too
How do I keep my child hydrated while they are home?
Small, frequent sips work better than big gulps. The AAP suggests offering small amounts of fluid every few minutes over a few hours, with a goal of at least 1 ounce (30 mL) per hour. A medicine cup, syringe, or spoon helps if they will not drink from a cup.
For about the first 24 hours, the AAP suggests limiting solid food and offering fluids often. If your child is otherwise healthy, skipping a meal or two while they are vomiting will not hurt them.
- Babies 6 to 12 months: keep giving breast milk or formula at full strength. If that is not kept down, use an oral rehydration solution. The AAP says not to use plain water to rehydrate a baby this age
- Kids 1 year and older: an oral rehydration solution (liquid or ice pops), or apple juice or a sports drink mixed half and half with water. The AAP notes sports drinks can be high in sugar, which can make diarrhea worse
- Medicine: the NHS says not to give medicine to stop diarrhea to children under 12, or aspirin to anyone under 16. Ask your child's doctor before giving any medicine for vomiting
When should you get care?
In an emergency, call 911Call your child's doctor right away if they cannot keep any clear liquids down, are too sick to drink, show signs of dehydration (peeing less, fewer than 6 wet diapers a day in a baby, a dry mouth or tongue, few or no tears, unusual sleepiness or fussiness, dizziness when standing), are very sleepy or floppy, have a swollen belly, or keep vomiting for more than 24 hours.
Call sooner if you are worried about a baby under 12 months, if your baby stops breast or bottle feeding, or if a young baby has forceful vomiting 15 to 30 minutes after every feed.
Call 911 or go to the ER if your child vomits blood or something that looks like coffee grounds, has green or yellow-green vomit, has a sudden severe belly ache or sudden severe headache, is confused or not responding as usual, has a stiff neck or pain looking at bright lights, has blue, gray, pale, or blotchy skin, lips, or tongue, is struggling to breathe or taking lots of quick, short breaths, or may have swallowed something poisonous.
How our AI doctor decides when to send you to care ›How do I stop it spreading at home and at school?
Soap and water is the main defense. The CDC says hand sanitizer does not work well against norovirus and is not a substitute for handwashing. Wash hands for at least 20 seconds after using the toilet, after changing diapers, after cleaning up vomit or soiled laundry, and before eating or making food.
For cleanup, the CDC recommends a bleach solution of 5 to 25 tablespoons of household bleach (5% to 8%) per gallon of water, left on the surface for at least 5 minutes. Take off and wash clothes or bedding with vomit or poop on them right away, using detergent and hot water on the longest cycle, then dry on the highest heat.
Common questions
When can my kid go back to school after vomiting?
Usually after at least 24 hours with no vomiting, once they are drinking normally and feel well enough to take part. For a stomach bug like norovirus, 48 hours after the last vomit or diarrhea is safer, and it is what the NHS advises. Check your school's written policy, since it decides.
My child threw up once and seems fine now. Do they have to stay home?
Not always. The AAP's child care guidance keeps kids home for 2 or more vomiting episodes in 24 hours, unless there is a non-infectious cause and no dehydration risk. One episode with a quick recovery may be fine, but your school may have its own rule, so check the policy.
Does the clock reset if they throw up again?
Yes. Count from the last time they vomited or had diarrhea. If it happens again, the 24 or 48 hours start over from that point.
Can my kid go to school if they still have diarrhea but stopped vomiting?
Usually not yet. The AAP says to keep kids home from child care if diarrhea leaks out of the diaper, causes accidents in a potty-trained child, means more than 2 extra stools in 24 hours, or has blood or mucus in it. The NHS counts 2 days from the end of both vomiting and diarrhea.
Can they go swimming after a stomach bug?
The NHS says not to use a swimming pool until at least 48 hours after symptoms stop. The CDC says norovirus can stay in poop for 2 weeks or more after your child feels better, so good handwashing still matters after that.
Is it a stomach bug or something else?
Most vomiting in kids is caused by a virus and gets better on its own. Green vomit, blood in the vomit, a swollen belly, severe belly pain, or vomiting that lasts more than 24 hours can point to other problems and needs a doctor.
Pymander is not a replacement for a physician and does not provide medical advice, diagnosis, or treatment. Always seek the advice of a qualified health provider with questions about a medical condition. If you think you may have a medical emergency, call 911.