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Fever in a baby or child: when to call, and what helps
For anyone looking after a baby or child with a fever: a parent, a grandparent, a sitter, at any hour. This page passes on, by name, what the National Library of Medicine, the National Institute of Neurological Disorders and Stroke (NINDS), CDC and the FDA say: what a fever is, the numbers that mean a call, why a fever in a baby under 3 months needs a call right away, liquids and the signs of drying out, what the pages say about fever medicine and at what ages, what to do during a seizure with a fever, and the signs that mean a call to the doctor or an emergency. It builds the questions to ask. Take only what you need tonight.
Right now
- Trouble breathing, blue lips, a child who is not alert, a seizure? On its flu page, CDC lists emergency warning signs in children and says people with these signs should obtain medical care right away: fast breathing or trouble breathing, bluish lips or face, ribs pulling in with each breath, chest pain, not alert or interacting when awake, seizures, and dehydration (no urine for 8 hours, dry mouth, no tears when crying). Ours: if your child is struggling to breathe, has blue lips, cannot be woken, or is having a seizure that lasts longer than five minutes, call 911.
- A baby under 3 months old with a fever of 100.4°F (38°C) or higher? CDC’s ear infection page says to talk to a healthcare provider right away. The FDA says to call a doctor for a fever of 100.4 degrees Fahrenheit or higher in an infant 2 months or younger. CDC’s flu page lists any fever in a child younger than 12 weeks among its emergency warning signs.
- A seizure? NINDS says: note the start time; put the child on the floor; do not restrain or hold the child; put the child on his or her side or stomach to prevent choking; nothing should ever be placed in the child’s mouth. If it lasts longer than five minutes, NINDS says to call an ambulance. If this is the child’s first febrile seizure, NINDS says to seek immediate medical attention.
- A fever above 104 degrees Fahrenheit that is not controlled by fever-reducing medicine is on CDC’s list of emergency warning signs in children. A fever of 102 degrees Fahrenheit or higher at any age: the FDA says to call a doctor. A fever that lasts longer than 4 days: CDC says to seek medical care.
- Never give aspirin to children. CDC says it can cause Reye’s syndrome. Younger than 6 months: CDC says only give acetaminophen.
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.
Changed on October 10, 2026. This box first gave lines from encyclopedia articles we should not have used. They are out; what is here now is CDC’s, the FDA’s, NINDS’s, or marked ours. The note at the bottom of the page says what changed.
More help
- A seizure, at any age: When someone has a seizure. First aid: First aid: what do you see?
- A baby who will not stop crying, and safe sleep: Crying baby: when the crying won’t stop.
- Counting wet diapers and feeds: Baby log. Writing down what happened and when: Symptom diary.
- Too much of a medicine, or the wrong one: When it might be a poisoning.
- A fever during chemotherapy: When the doctor says cancer.
- 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.
Looking after a baby or child? The pages on this site for a baby or child, on one list.
Other guides on this site that go with this page
Free to read. We chose these ourselves; no professional did. Each guide was written with AI and has not been reviewed by a professional. They are general information, not advice.
- Hydronephrosis in newborns (a swollen kidney in a baby): the causes, the tests, and the treatment: hydronephrosis in a newborn (a swollen kidney in a baby, found on a pregnancy ultrasound or after birth): what it is and how common, when it is a sign of a problem, the causes, the tests before and after birth, and the treatment.
- Kidney infection (pyelonephritis): the signs, sepsis, and the treatment: a kidney infection (pyelonephritis): the signs at each age, sepsis and when it is 911, who is more likely to get one, the tests, the antibiotics, and preventing the next one.
This page and its wording were written with AI (Claude) for Scarlet Beast (our AI policy). No doctor, nurse or pharmacist has reviewed it. Changed on October 10, 2026. When this guide was published on October 9, most of it passed on four articles of a medical encyclopedia that is licensed text; its publisher’s notice does not allow that reuse, including by AI. We had decided not to use such articles and then did. That was our mistake. Every line from them is out. What the page passes on now, read on October 9 and 10, 2026: the Summary of the Fever health topic page on MedlinePlus, which the National Library of Medicine writes (we pass on only that Summary, in English and Spanish, not the pages it links to); Febrile Seizures, from the National Institute of Neurological Disorders and Stroke (last reviewed March 13, 2026; English and Spanish); five CDC pages: Signs and Symptoms of Flu (August 26, 2024), Ear Infection Basics (reviewed April 17, 2024), Manage Common Cold (updated March 11, 2026) and Preventing Spread of Respiratory Viruses When You’re Sick (reviewed August 18, 2025), each in English and Spanish, and Febrile Seizures and Vaccines (updated December 20, 2024; English only); and two FDA pages: Should You Give Kids Medicine for Coughs and Colds? (current as of November 7, 2024; English and Spanish) and Non-contact Infrared Thermometers (current as of March 6, 2026; English only). Most of these pages were not written about fever alone. The lists of when to call come from pages about the flu, a cold, a cough and an ear infection, and the page says so each time; no federal page we found and may pass on is a single guide to fever in a child. Where the sources differ, the page gives each: the youngest babies are “under 3 months old” on one CDC page, “younger than 12 weeks” on another, and “2 months or younger” for the FDA; the fever numbers for a call are 102, 102.2 and 104 degrees Fahrenheit on three pages about three illnesses; NINDS says most febrile seizures are over within a couple minutes and CDC says less than one or two; CDC says febrile seizures do not cause any permanent harm, and NINDS says longer seizures raise the risk of epilepsy. What is gone because no page we may pass on says it: a fever number for each place a temperature is taken, and how to take one; which thermometer to choose; how high a fever goes and when it can do harm; teething; the signs that an illness is probably mild; how to dress a child with a fever, the room, and baths; what to give to drink and eat; the list of signs for 911 and the list for the provider, with their ages and hours; using two medicines; and several lines about what to do during and after a seizure. For those, ask your child’s provider. What is marked “ours” is our own, including every line that names 911: none of the pages names it. What we left out: every brand name; every amount of medicine and how often it is given; fever in an adult; NINDS’s research section; and what CDC says about particular vaccines. We called no number. It saves nothing and loads no tracking.