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What should I do if my child has gastroenteritis?
Gastroenteritis is usually mild, but the main risk is dehydration. Here is how to help at home and when to get care.
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What it is
Gastroenteritis is an inflammation of the lining of the stomach and intestines [2]. The main symptoms are vomiting and diarrhoea [2]. It is usually not serious in healthy people, but it can sometimes lead to dehydration or cause severe symptoms [2].
There are many possible causes: viruses, bacteria, parasites, chemicals, and reactions to certain medicines and food [2]. Viral gastroenteritis is the most common type, and it can be caused by viruses including noroviruses and rotaviruses [2]. Some people call viral gastroenteritis the “stomach flu”, but this name is not medically correct — it is not caused by flu viruses [2]. Norovirus is a very contagious virus that causes vomiting and diarrhoea, and most people with norovirus illness get better within 1 to 3 days [5].
When gastroenteritis is caused by eating or drinking food or drinks contaminated with viruses, bacteria, parasites or chemicals, this is called food poisoning [2]. These germs can also spread from person to person, for example when you touch something that has germs on it and then touch your eyes, mouth or nose [2].
Symptoms include diarrhoea, pain or cramping in the abdomen (belly), nausea, vomiting and sometimes fever [4]. Some people are at higher risk of dehydration or severe symptoms: pregnant women, older adults, people with weakened immune systems or other serious health conditions, infants, and babies born prematurely or with other health conditions [4]. If you or a family member are at higher risk and have symptoms of gastroenteritis, contact a health care provider right away [4].
What you can do at home
- The most important thing is to prevent dehydration from the fluid lost through stools and vomiting [8].
- Oral rehydration solutions contain water, sugar and salts (sodium, potassium, chlorine) in a precise proportion to replace these losses [8]. Give your child the amount you have been told to give after each watery stool or each vomit [8]. Offer them in small doses and frequent sips so they are well tolerated [8].
- Do not use homemade solutions or commercial soft drinks to replace the losses caused by gastroenteritis [7].
- Do not give your child medicines for diarrhoea or vomiting without consulting your paediatrician [7].
- Fasting is not necessary: children should keep eating a practically normal diet unless a doctor says otherwise [6]. Give food in smaller amounts to reduce the risk of vomiting, and more often, respecting the child’s appetite [6].
- Avoid foods rich in fat, which are harder to absorb, and also avoid sweets and juices [6].
- It is not necessary to avoid dairy products [6]. Keep breastfeeding normally, and even more often if the child asks for it [6].
- Sports drinks should be avoided because they have too much sugar and electrolyte levels that are not suitable for a child with diarrhoea [6].
- When your child vomits, it is recommended to wait 20 minutes and then give oral rehydration solution, 2–5 ml every 5 minutes for one hour [10]. Watch how well your child accepts it; if fluids are well tolerated, you can slowly increase the frequency [10].
- Frequent hand washing of the patient and the carers is essential to avoid spreading the illness; an alcohol-based solution can be used as an alternative [7].
When to see a doctor or go to the emergency department
For adults, contact a provider right away if there is: a change in mental state such as irritability or lack of energy; diarrhoea lasting more than 2 days; high fever; vomiting often; six or more loose stools in a day; severe pain in the abdomen or rectum; stools that are black and tarry or contain blood or pus; or symptoms of dehydration such as thirst, dry mouth, headache, dark-coloured urine and urinating less than normal [4].
For infants and children, contact a provider right away if there is: a change in the child’s mental state such as irritability or lack of energy; diarrhoea lasting more than a day; any fever in infants; high fever in older children; frequent loose stools; vomiting often; severe pain in the abdomen or rectum; signs of dehydration such as thirst, dry mouth, urinating less than usual or no wet diapers for 3 hours or more, and no tears when crying; or stools that are black and tarry or contain blood or pus [4].
Also seek care again at the emergency department if the child vomits a lot, cannot tolerate solids or liquids, or vomits even when taking nothing; if the vomit is greenish, contains blood, or looks like brown coffee grounds; if the child is very thirsty, cries without tears, urinates little or has sunken eyes; if the child is markedly irritable, drowsy or less responsive; if the stools are very watery, large and frequent so that the child cannot drink as fast as they are losing fluid; if the child refuses to eat or drink; or if there is persistent or intense abdominal pain or stools with a lot of blood [6][7].
Common questions
Can gastroenteritis be prevented? It cannot always be prevented [1]. But proper hand washing, cleaning surfaces that may be infected with germs, and safe food preparation may help prevent some of the infections that cause it [1]. There are vaccines for infants to protect against rotavirus infections [1].
Does my child need medicine? Usually people with gastroenteritis get better on their own, with rest and plenty of fluids and electrolytes [3]. Your provider may suggest a probiotic, as studies suggest some probiotics may help shorten a case of diarrhoea [3]. People with more severe symptoms may need medicines to control nausea or vomiting, and providers may give other medicines for certain types, such as antibiotics for some bacterial types and antiparasitic medicines for some parasitic types [3].
How is it diagnosed? Your provider will do a physical exam, ask about your symptoms, and may do tests of your stool [4].
Sources
[1] MedlinePlus — “Gastroenteritis” (2022), section “Can gastroenteritis be prevented?”, p. 1 — https://medlineplus.gov/gastroenteritis.html [2] MedlinePlus — “Gastroenteritis” (2022), section “What is gastroenteritis?”, p. 1 — https://medlineplus.gov/gastroenteritis.html [3] MedlinePlus — “Gastroenteritis” (2022), section “What are the treatments for gastroenteritis?”, p. 1 — https://medlineplus.gov/gastroenteritis.html [4] MedlinePlus — “Gastroenteritis” (2022), section “What are the symptoms of gastroenteritis?”, p. 1 — https://medlineplus.gov/gastroenteritis.html [5] CDC — “About Norovirus”, section “More Information What it is”, p. 1 — https://www.cdc.gov/norovirus/about/index.html [6] SEUP — “Gastroenteritis aguda. Información para padres” (2025), section “¿DEBEMOS OFRECERLE ALGUNA ALIMENTACIÓN ESPECIAL?”, p. 1 [7] SEUP — “Gastroenteritis aguda. Información para padres” (2025), section “Ofrecer en pequeñas cantidades SRO Dolor abdominal”, p. 2 [8] SEUP — “Gastroenteritis aguda. Información para padres” (2025), section “¿QUÉ ES LA GASTROENTERITIS AGUDA? ¿CUÁLES SON LOS SÍNTOMAS?”, p. 1 [10] SEUP — “Vómitos. Información para padres” (2025), section “¿QUÉ PODEMOS HACER EN CASA CUANDO TIENE VÓMITOS?”, p. 1
This guide summarises published paediatric guidelines. It is not medical advice and does not replace your paediatrician. In an emergency, call your local emergency number.
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