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Vomiting and diarrhea in a baby or child: fluids, and when to call
For anyone looking after a baby or child who is throwing up or has diarrhea: a parent, a grandparent, a sitter, at any hour. This page passes on, by name, what MedlinePlus and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) say: the signs of dehydration, how to give liquid a little at a time, what the pages say to give and where they disagree, feeding a baby, what to eat, why diarrhea medicine is not for children unless a provider says so, how to keep it from spreading, and the signs that mean a call to the doctor or 911. It builds the questions to ask. Take only what you need tonight.
Right now
- Call 911 if your child loses consciousness at any time, or if there is any other change in their alertness (for example, confusion or seizures). Those lines are from MedlinePlus’s Dehydration page, which says severe dehydration is a life-threatening emergency.
- Call 911 or go to an emergency room if you think the vomiting is from poisoning, or you notice blood or dark, coffee-colored material in the vomit. That is from MedlinePlus’s page on nausea and vomiting, which is written for adults. For something a child may have swallowed, see When it might be a poisoning.
- A baby under 3 months old with diarrhea? MedlinePlus says to contact your provider. NIDDK says to seek a doctor’s help right away when an infant has signs of viral gastroenteritis.
- Signs of dehydration? No tears when crying, a dry and sticky mouth, sunken eyes, a sunken soft spot on a baby’s head, or hours with no wet diaper (NIDDK says 3 hours or more; MedlinePlus’s pages say 6, and 8). NIDDK says anyone with signs or symptoms of dehydration should see a doctor right away.
- Give liquid a little at a time. MedlinePlus says: if your baby throws up, start with as little as 1 teaspoon (5 ml) of liquid every 10 to 15 minutes, and do not try to force down large amounts at one time.
- Do not give a child medicine to stop diarrhea unless your child’s provider says it is OK. That is MedlinePlus’s line, and NIDDK says these medicines can be unsafe for infants and children.
If you cannot reach a provider and you are frightened for your child, go to an emergency room or call 911. That line is ours. This page is not for emergencies.
More help
- A fever with it: Fever in a baby or child: when to call, and what helps.
- Something a child may have swallowed: When it might be a poisoning. First aid: First aid: what do you see?
- Counting wet and dirty diapers and feeds: Baby log. Writing down what happened and when: Symptom diary.
- Breastfeeding through an illness: Breastfeeding: when it hurts, or you’re not sure it’s working.
- A baby who will not stop crying: Crying baby: when the crying won’t stop.
- For a visit: Get ready for your appointment. No insurance: When you need a doctor and can’t pay.
- A newborn at home: Pregnant, or with a new baby.
- All our free tools.
This page and its wording were written with AI (Claude) for Scarlet Beast (our AI policy). No doctor, nurse or pharmacist has reviewed it. The facts were read on October 9, 2026 on two government websites, every page in English and in Spanish. On MedlinePlus, from the National Library of Medicine, five pages of its Medical Encyclopedia: Diarrhea in infants (reviewed July 1, 2025), When your child has diarrhea (for children over 1 year of age; reviewed October 1, 2025), Viral gastroenteritis (stomach flu) (reviewed April 27, 2026), Dehydration (reviewed July 1, 2025), and Nausea and vomiting – adults (reviewed July 22, 2025), from which we took only the two lines on 911. On niddk.nih.gov, three pages on viral gastroenteritis: Symptoms & Causes, Treatment, and Eating, Diet, & Nutrition; each says “Last Reviewed May 2018”, so they are older than the MedlinePlus pages. The page says whose words it is passing on, and what is marked “ours” is our own. Where the sources differ, the page gives each: hours without a wet diaper or urine are 3 or more on NIDDK, 6 on two MedlinePlus pages and 8 or more on a third; one MedlinePlus page allows watered-down fruit juice, broth and gelatin, and another says not to use fruit juice, gelatin or broth; sports drinks are “ask your provider” on one page, “should be avoided” on another, and not for young infants on a third; NIDDK says a restricted diet does not help, and MedlinePlus says children often do better with bland foods and gives lists; how long before a call is more than a day on NIDDK, and 24 hours of vomiting, 2 to 3 days of fever and diarrhea, or “several days” on MedlinePlus’s pages. MedlinePlus’s Dehydration page, written for any age, lists a fever over 102°F (38.8°C) under calling 911; its fever pages use other numbers by age, and this page says so. What we left out or did not read: every brand name (the pages name electrolyte drinks, a sports drink, a gelatin, diarrhea medicines and the rotavirus vaccines); the name and amount of every medicine; the adult lists on NIDDK and on MedlinePlus’s nausea page, including its adult thresholds for calling; the tests done at a visit; the rarer viruses; NIDDK’s pages on definition, diagnosis and clinical trials; MedlinePlus’s patient pages on nausea and on clear liquid diets; anything from the CDC directly (NIDDK cites it for cleaning and for food handling); food poisoning as its own subject; long-lasting (chronic) diarrhea; reflux and spitting up in babies; and when a child may go back to child care or school, which the pages we read do not say. We called no number. It saves nothing and loads no tracking.