RCH logo

Kids Health Info

Gastroenteritis (gastro)

  • Translated resources

    This page is available in 16 community languages.

    Please note: the information on these translated pages is not an exact translation of this page.

    Key points

    • Gastroenteritis (gastro) is an infection of the stomach and bowel.
    • It causes vomiting, fever and diarrhoea (runny, watery poo).
    • The most important part of caring for a child with gastro is ensuring they drink enough fluids. Try giving your child small amounts of fluid often.
    • Gastro is very contagious; it is important to practice good hygiene to stop the spread.
    • Watch your child for signs of dehydration, such as less wet nappies or not going to the toilet often, dark yellow or brown pee, or dry lips and mouth. If you are worried, speak to a doctor.

    What is gastro?

    Gastroenteritis (gastro) is an infection of the stomach and intestines (bowel). In most cases, gastro starts with vomiting and then leads to diarrhoea (runny, watery poo). The vomiting may settle quickly, but the diarrhoea can last up to 10 days.

    Many germs can cause gastro, but a virus is the most common.

    Gastro spreads easily and is more common and severe in babies and young children.

    Signs and symptoms of gastro

    If your child has gastro, they may:

    • feel unwell and not want to eat or drink
    • vomit in the first 24 to 48 hours
    • have diarrhoea
    • have cramping stomach pain that comes and goes
    • have a fever.

    The first few days of the infection are usually the hardest to manage – especially if your child is vomiting.

    Some children are more likely to get dehydrated. These include:

    • babies under six months
    • people with long-term health issues, such as chronic bowel disease or kidney disease.

    How to care for gastro at home

    Unfortunately, there is no medicine to cure gastro. Over-the-counter medicines that reduce vomiting and diarrhoea may be harmful for children. If your child has severe nausea and vomiting, a doctor may prescribe ondansetron to help with this.

    Hydration is the key to caring for gastro at home, but it can be hard to ensure your child drinks enough fluids when they are vomiting and do not want to drink. Try to give your child small amounts of fluid often – even if they are vomiting. This will help replace any fluids they lose due to vomiting and diarrhoea.

    Caring for infants under six months

    Babies under six months old are at higher risk of dehydration, so you should take them to see a doctor or health professional if they show signs of gastro.

    • If breastfeeding your baby, continue to do so, but feed more often. You can also give your baby an oral rehydration solution for the first 12 hours.
    • If you are bottle feeding with formula, try feeding small amounts often. If they are not keeping fluids down, switch to an oral rehydration solution for 12 hours, then go back to the formula in small amounts regularly. The formula should be normal strength, not diluted.
    • Offer your baby a drink every time they vomit.

    Caring for children between six months and three years

    • If breastfeeding your baby, continue to do so, but feed more often. Offer them a drink every time they vomit.
    • When your child is vomiting, try giving them small amounts of half-strength apple juice mixed with water or oral rehydration solution (liquid or icy poles) regularly until the vomiting settles down.
    • You can continue formula feeding and giving milk; however, the body cannot absorb these fluids as easily if your child is actively vomiting.
    • Flat lemonade, sports drinks and fortified feeds are high in sugar and can make dehydration worse. Avoid giving these to your child while they are sick.
    • The most important thing is getting your child have some fluids. You can try giving them a regular icy pole if they do not want to drink juice or oral rehydration solution.
    • Offer your child a drink every time they vomit.
    • If your child is very young and will not drink anything, you can try giving them fluid with a syringe the same way you give medicine.

    Caring for older children

    • Give your child small amounts of fluid often – a few mouthfuls every five to 15 minutes.
    • If your child does not want to drink water, you can try an oral rehydration solution, but some do not like the salty taste. Instead, try giving them a normal icy pole or half-strength apple juice mixed with water.
    • Paracetamol can help if your child is in pain. Do not give them aspirin.

    Signs to seek medical care

    Your child may need care in hospital if you have tried everything to keep them hydrated but they are showing signs of dehydration. This care may involve fluids through a nasogastric tube or IV drip.

    If your child shows any of the following signs, it is best to speak with their doctor:

    • Their condition is getting worse, not better.
    • They have constant stomach pain (it does not come and go)
    • They have severe stomach pain
    • They have constant pain in their lower right side
    • They do not want to move around or walk
    • They have persistent vomiting but no diarrhoea
    • They have khaki-green-coloured vomit.

    Is gastro contagious?

    Gastro is very contagious. It spreads through contact with the vomit or poo of an infected person, for example, by touching someone who has recently thrown up or had diarrhoea, sharing contaminated food or drinks, or touching contaminated objects like toys. Gastro can also spread through the air when an infected person vomits.

    Stopping the spread of gastro

    Good hygiene is the best way to limit the spread of gastro. If your child has gastro, remember to:

    • wash your hands thoroughly with soap or alcohol hand sanitiser – especially before and after touching your child, feeding, and nappy changes.
    • regularly wash and/or disinfect objects like toys, clothes and bedding.
    • clean shared surfaces like tables and door handles.
    • stop other members of your household from sharing items with your sick child.

    It is a good idea to wear gloves and a mask when cleaning up vomit or poo. Use disposable cleaning products like paper towels and put them into a bag before throwing them away.

    When to get help

    Call an ambulance (000) if:
    • your child is unconscious, very lethargic (low energy) or hard to wake.

    Go to a hospital if:
    • your child cannot keep any fluids down without vomiting and shows several signs of dehydration, such as less wet nappies or not going to the toilet often, dark yellow or brown pee, dry lips and mouth, or feeling light-headed or dizzy.
    • your child has khaki green vomit (yellow vomit is usually not a concern).

    See a doctor or health professional if:
    • your child is under six months old and is vomiting or has a fever.
    • your child is vomiting, has diarrhoea and is not drinking enough fluids.
    • your child has a lot of diarrhoea (eight to 10 watery poos per day).
    • your child’s diarrhoea is not getting better after 10 days.
    • your child shows signs of dehydration, such as less wet nappies or not going to the toilet often, dark yellow or brown pee, dry lips and mouth, light-headedness or dizziness.
    • your child has constant stomach pain that does not come and go, is getting worse or does not get better with paracetamol.
    • your child has blood in their poo.
    • your child caught their illness overseas.

    Look after your child at home if:
    • they are drinking enough fluids and staying hydrated.
    • your child starts getting better within a few days.

    Common questions about gastro

    I am worried the fluids I am giving my child are making their diarrhoea worse. Should I give them less to drink?

    While the fluids may seem to pass straight through, your child will still absorb a lot of what you give them. It is important to give your child at least as many fluids as they are losing through vomiting and diarrhoea.

    Should I be worried that my child does not want to eat when they have gastro?

    When your child first gets gastro, they may refuse food. This is not a problem if they are drinking enough fluids. Give them the food again when they feel like eating; this is usually after they have stopped vomiting and do not feel as nauseated.

    Can my child have dairy after a bout of gastro?

    Most children do not have a problem digesting dairy foods after gastro. Some will get a temporary inability to digest dairy sugar (lactose). This produces lots of wind and acidic diarrhoea. If you notice your child gets symptoms after having dairy, you can reduce their dairy intake for around three weeks following their gastro.

    What should I feed my child when they have gastro?

    There are no specific dietary restrictions for children during or after gastro. It is best to let your child’s appetite guide you. Sometimes fatty or dairy-containing foods are not tolerated as well as other foods, but you will not know until you try them. The bowel heals quicker with food inside it.

    When can my child go back to school or childcare after gastro?

    Your child can return to school or childcare once they feel better and have not had any diarrhoea or vomiting for 48 hours. However, they should not go back to swimming for two weeks after recovering to help prevent the spread of the illness.

    There is blood in my child’s poo. Should I be worried?

    Blood in poo is common with gastro. While it is scary to see, it is rarely a problem. You may want to speak to your child’s doctor about testing the poo for a food poisoning germ. This testing aims to track down a food poisoning outbreak for public health reasons.

    A doctor thinks my child has bacterial gastro. Do we need antibiotics?

    Even though bacteria occasionally cause gastro, doctors rarely suggest treating it with antibiotics. Most children will get better on their own, and antibiotics can cause serious complications such as allergies or antibiotic-associated diarrhoea.

    How long is it normal for diarrhoea to last after gastro?

    After 14 days of diarrhoea, it is best to speak with a doctor about your child’s condition. A poo sample analysis might be useful in case they have an unusual germ.

    Do you need to test my child’s poo?

    It is usually not necessary to test your child’s poo when they have gastro. Almost all gastro is treated the same way, so knowing the cause will not change the treatment. In most cases, poo is only tested when it contains blood or if the diarrhoea has been going on for more than 14 days.

    My child caught gastro while overseas. What do I do?

    Speak with a doctor if your child caught gastro overseas. There are some differences in care and testing for children who get sick while travelling.

      This podcast is also available in audio format below, and on Apple Podcasts and Spotify.

      Podcast Image

      Winter wellness season: Gastro and why it peaks in winter

      For more information

      Developed by The Royal Children’s Hospital Emergency department. We acknowledge the input of RCH consumers and carers.

      Reviewed May 2025

      Please always seek the most recent advice from a registered and practising clinician.


    Disclaimer

    This information is intended to support, not replace, discussion with your doctor or healthcare professionals. The authors of these consumer health information handouts have made a considerable effort to ensure the information is accurate, up to date and easy to understand. The Royal Children's Hospital Melbourne accepts no responsibility for any inaccuracies, information perceived as misleading, or the success of any treatment regimen detailed in these handouts. Information contained in the handouts is updated regularly and therefore you should always check you are referring to the most recent version of the handout. The onus is on you, the user, to ensure that you have downloaded the most up-to-date version of a consumer health information handout.