Medical Conditions

Baby Has a High Fever Over 104 Degrees F

Medically reviewed by Dr. Michael Okonkwo, MD, FAAP · Board-Certified Neonatologist

Content reviewed against published AAP, AAP, NIH guidelines

Editorial policy

Last reviewed:

If your baby has been diagnosed with or you suspect baby has a high fever over 104 degrees f, here is what the evidence says.

The short answer

A fever above 104 degrees F (40 degrees C) in a baby or toddler can be alarming, but the height of the fever alone does not necessarily indicate a more serious illness. Many common childhood viral infections (like roseola) can cause high fevers. What matters more than the number is how your child looks and behaves. A child with a 104 degree F fever who is still alert, making eye contact, and drinking fluids is less concerning than a child with a 102 degree F fever who is limp and unresponsive. However, fevers above 104 degrees F should always be discussed with your pediatrician.

Key takeaways

  • A fever above 104 degrees F (40 degrees C) in a baby or toddler can be alarming, but the height of the fever alone does not necessarily indicate a more serious illness. Many common childhood viral infections (like roseola) can cause high fevers. What matters more than the number is how your child looks and behaves. A child with a 104 degree F fever who is still alert, making eye contact, and drinking fluids is less concerning than a child with a 102 degree F fever who is limp and unresponsive. However, fevers above 104 degrees F should always be discussed with your pediatrician.
  • Usually normal when: A fever up to 104 degrees F during a common viral illness with a child who is still alert and drinking
  • Call your doctor if: ANY fever in a baby under 3 months (100.4 degrees F or higher) - go to the ER
“Fever itself is not an illness — rather, it is a sign or symptom that the body is fighting an infection. Fever stimulates certain defenses, such as the white blood cells, which attack and destroy invading bacteria.”
— Fever and Your Child, American Academy of Pediatrics (AAP)

Thousands of parents search for this exact thing. You are not alone.

What Parents Should Know

According to AAP, NIH guidelines, a fever above 104 degrees F (40 degrees C) in a baby or toddler can be alarming, but the height of the fever alone does not necessarily indicate a more serious illness. Many common childhood viral infections (like roseola) can cause high fevers. What matters more than the number is how your child looks and behaves. A child with a 104 degree F fever who is still alert, making eye contact, and drinking fluids is less concerning than a child with a 102 degree F fever who is limp and unresponsive. However, fevers above 104 degrees F should always be discussed with your pediatrician. At 0-12 months, for babies under 3 months, ANY fever of 100.4 degrees F or higher is a medical emergency - go to the ER immediately regardless of how the baby looks (see our newborn fever page). For babies 3-12 months, a fever above 104 degrees F should prompt a call to your pediatrician or an ER visit. Give appropriately dosed acetaminophen (age 2 months+) or ibuprofen (age 6 months+). Keep your baby hydrated with frequent breast milk or formula. Dress in light clothing. Do NOT give ice baths or cold water baths - lukewarm baths are OK. If the fever does not respond to medication at all, seek medical attention. It is generally considered normal when a fever up to 104 degrees F during a common viral illness with a child who is still alert and drinking. However, you should contact your pediatrician promptly if aNY fever in a baby under 3 months (100.4 degrees F or higher) - go to the ER.

Sources: [1], [2], [3]

Normal vs. Concerning

Usually Normal
Worth Discussing
A fever up to 104 degrees F during a common viral illness with a child who is still alert and drinking
ANY fever in a baby under 3 months (100.4 degrees F or higher) - go to the ER
Fever that comes down with medication even if it returns when the medication wears off
Fever above 104 degrees F that does not respond to medication at all
Mild irritability and decreased appetite with a fever
Fever with a stiff neck, severe headache, or persistent vomiting (possible meningitis)

When to Seek Immediate Care

  • ANY fever in a baby under 3 months (100.4 degrees F or higher) - go to the ER
  • Fever above 104 degrees F that does not respond to medication at all
  • Fever with a stiff neck, severe headache, or persistent vomiting (possible meningitis)
  • Fever with a purple or dark red rash that does not blanch (petechiae/purpura)
  • Your child is limp, unresponsive, or very difficult to wake
  • Fever with difficulty breathing
  • Febrile seizure (convulsion with fever) - call 911
  • Fever above 106 degrees F - emergency

By Age

What to expect by age

0-12 months

For babies under 3 months, ANY fever of 100.4 degrees F or higher is a medical emergency - go to the ER immediately regardless of how the baby looks (see our newborn fever page). For babies 3-12 months, a fever above 104 degrees F should prompt a call to your pediatrician or an ER visit. Give appropriately dosed acetaminophen (age 2 months+) or ibuprofen (age 6 months+). Keep your baby hydrated with frequent breast milk or formula. Dress in light clothing. Do NOT give ice baths or cold water baths - lukewarm baths are OK. If the fever does not respond to medication at all, seek medical attention.

1-3 years

A fever above 104 degrees F in a toddler should be managed and monitored carefully. Give acetaminophen or ibuprofen at the correct weight-based dose. Ensure your child is drinking fluids. Focus on how your child looks and acts: are they making eye contact? Can they be comforted? Are they taking fluids? A child who is playing and interactive between fever spikes is less concerning than one who is persistently lethargic. Call your pediatrician if: fever above 104 degrees F lasts more than 24 hours, your child looks very ill, fever is accompanied by a stiff neck, severe headache, or rash, or the fever does not come down at all with medication.

What to Tell Your Pediatrician

  • Describe when you first noticed baby has a high fever over 104 degrees f and how it has changed over time.
  • Note your baby's current age and which age-specific patterns you are seeing.
  • Mention if any fever above 104 degrees F - call your pediatrician for guidance.
  • Mention if fever above 102 degrees F lasting more than 2-3 days.
  • Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
  • Bring a list of any questions or observations you want to discuss at the appointment.

What Should You Do?

When to take action

Probably normal when...
  • A fever up to 104 degrees F during a common viral illness with a child who is still alert and drinking
  • Fever that comes down with medication even if it returns when the medication wears off
  • Mild irritability and decreased appetite with a fever
Mention at your next visit when...
  • Any fever above 104 degrees F - call your pediatrician for guidance
  • Fever above 102 degrees F lasting more than 2-3 days
  • You are unsure about medication dosing for fever
  • Your child has a fever and you are concerned about their behavior
Act now when...
  • ANY fever in a baby under 3 months (100.4 degrees F or higher) - go to the ER
  • Fever above 104 degrees F that does not respond to medication at all
  • Fever with a stiff neck, severe headache, or persistent vomiting (possible meningitis)
  • Fever with a purple or dark red rash that does not blanch (petechiae/purpura)
  • Your child is limp, unresponsive, or very difficult to wake
  • Fever with difficulty breathing
  • Febrile seizure (convulsion with fever) - call 911
  • Fever above 106 degrees F - emergency

What You Can Do at Home

  • Keep track of when you notice baby has a high fever over 104 degrees f — noting the time of day, duration, and any triggers can help your pediatrician.
  • Remember that a fever up to 104 degrees F during a common viral illness with a child who is still alert and drinking — this is generally within the range of normal.
  • At 0-12 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
  • Follow any care instructions from your pediatrician. Keep a written log of symptoms to bring to appointments.
  • While monitoring at home, seek immediate care if aNY fever in a baby under 3 months (100.4 degrees F or higher) - go to the ER.

Fever in a Baby Under 3 Months Old

A fever in a baby under 3 months old (temperature of 100.4 degrees F / 38 degrees C or higher taken rectally) is always a medical emergency. Go to the emergency room immediately, regardless of how well your baby appears. Young babies' immune systems cannot fight infections as effectively as older children, and a fever could indicate a serious bacterial infection (urinary tract infection, bacteremia, or meningitis) that needs urgent treatment. Do NOT wait to see if the fever goes down. Do NOT give fever medication and stay home - go to the ER first.

Ibuprofen and Acetaminophen Dosing Safety

Acetaminophen (Tylenol) can be given to babies 2 months and older. Ibuprofen (Motrin/Advil) should NOT be given to babies under 6 months. Dosing is based on your child's WEIGHT, not age - always use the dosing syringe that comes with the product and follow the weight-based chart on the packaging. Never give aspirin to children under 18 (risk of Reye syndrome). When in doubt about dosing, call your pediatrician. Alternating acetaminophen and ibuprofen can be effective for fever but increases the risk of dosing errors - only do this under your pediatrician's guidance.

febrile seizures

Cold vs. Flu in Baby - How to Tell the Difference

Colds and flu are both respiratory illnesses but are caused by different viruses and differ in severity. A cold comes on gradually with runny nose, sneezing, and mild cough. The flu hits suddenly with high fever, body aches, extreme fatigue, and a dry cough. Babies and children under 5 are at higher risk for flu complications. The flu can be treated with antiviral medication (like oseltamivir/Tamiflu) if started within 48 hours of symptom onset, which is why early evaluation is important. The best prevention is the annual flu vaccine, recommended for all children 6 months and older.

Triage

Fever Decision Tree

Step-by-step guidance for evaluating your baby's fever by age and temperature.

Guide

When to Call the Doctor

General guide on when to call the pediatrician, visit urgent care, or go to the ER.

Frequently asked questions

Is baby has a high fever over 104 degrees f normal?
A fever above 104 degrees F (40 degrees C) in a baby or toddler can be alarming, but the height of the fever alone does not necessarily indicate a more serious illness. Many common childhood viral infections (like roseola) can cause high fevers. What matters more than the number is how your child looks and behaves. A child with a 104 degree F fever who is still alert, making eye contact, and drinking fluids is less concerning than a child with a 102 degree F fever who is limp and unresponsive. However, fevers above 104 degrees F should always be discussed with your pediatrician.
When should I call the doctor about baby has a high fever over 104 degrees f?
ANY fever in a baby under 3 months (100.4 degrees F or higher) - go to the ER Fever above 104 degrees F that does not respond to medication at all Fever with a stiff neck, severe headache, or persistent vomiting (possible meningitis)
When is baby has a high fever over 104 degrees f normal?
A fever up to 104 degrees F during a common viral illness with a child who is still alert and drinking Fever that comes down with medication even if it returns when the medication wears off Mild irritability and decreased appetite with a fever
What causes baby has a high fever over 104 degrees f?
A fever above 104 degrees F (40 degrees C) in a baby or toddler can be alarming, but the height of the fever alone does not necessarily indicate a more serious illness. Many common childhood viral infections (like roseola) can cause high fevers. What matters more than the number is how your child looks and behaves. A child with a 104 degree F fever who is still alert, making eye contact, and drinking fluids is less concerning than a child with a 102 degree F fever who is limp and unresponsive. However, fevers above 104 degrees F should always be discussed with your pediatrician. Common explanations include: A fever up to 104 degrees F during a common viral illness with a child who is still alert and drinking. Fever that comes down with medication even if it returns when the medication wears off.
What should I mention to my pediatrician about baby has a high fever over 104 degrees f?
You should mention baby has a high fever over 104 degrees f at your next visit if: Any fever above 104 degrees F - call your pediatrician for guidance. Fever above 102 degrees F lasting more than 2-3 days. You are unsure about medication dosing for fever.
Is baby has a high fever over 104 degrees f normal at 0-12 months?
For babies under 3 months, ANY fever of 100.4 degrees F or higher is a medical emergency - go to the ER immediately regardless of how the baby looks (see our newborn fever page). For babies 3-12 months, a fever above 104 degrees F should prompt a call to your pediatrician or an ER visit. Give appropriately dosed acetaminophen (age 2 months+) or ibuprofen (age 6 months+). Keep your baby hydrated with frequent breast milk or formula. Dress in light clothing. Do NOT give ice baths or cold water baths - lukewarm baths are OK. If the fever does not respond to medication at all, seek medical attention.
Is baby has a high fever over 104 degrees f normal at 1-3 years?
A fever above 104 degrees F in a toddler should be managed and monitored carefully. Give acetaminophen or ibuprofen at the correct weight-based dose. Ensure your child is drinking fluids. Focus on how your child looks and acts: are they making eye contact? Can they be comforted? Are they taking fluids? A child who is playing and interactive between fever spikes is less concerning than one who is persistently lethargic. Call your pediatrician if: fever above 104 degrees F lasts more than 24 hours, your child looks very ill, fever is accompanied by a stiff neck, severe headache, or rash, or the fever does not come down at all with medication.
Should I go to the ER for baby has a high fever over 104 degrees f?
Seek emergency care if aNY fever in a baby under 3 months (100.4 degrees F or higher) - go to the ER, or if fever above 104 degrees F that does not respond to medication at all. When in doubt, call your pediatrician's after-hours line for guidance.
Does baby has a high fever over 104 degrees f go away on its own?
In many cases, baby has a high fever over 104 degrees f resolves on its own, especially when a fever up to 104 degrees F during a common viral illness with a child who is still alert and drinking.
AAPAAPNIH

References

  1. [1]American Academy of Pediatrics. Fever. HealthyChildren.org. AAP
  2. [2]American Academy of Pediatrics. When to Call the Pediatrician: Fever. HealthyChildren.org. AAP
  3. [3]National Library of Medicine. Fever in Children. StatPearls. NIH

Doctor Visit Checklist

Bring this checklist to your next pediatrician visit to discuss Baby Has a High Fever Over 104 Degrees F.

Things to mention

  • Describe when you first noticed baby has a high fever over 104 degrees f and how it has changed over time.
  • Note your baby's current age and which age-specific patterns you are seeing.
  • Mention if any fever above 104 degrees F - call your pediatrician for guidance.
  • Mention if fever above 102 degrees F lasting more than 2-3 days.
  • Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
  • Bring a list of any questions or observations you want to discuss at the appointment.

Observations to share

  • Any fever above 104 degrees F - call your pediatrician for guidance
  • Fever above 102 degrees F lasting more than 2-3 days
  • You are unsure about medication dosing for fever

Urgent signs to report immediately

  • ANY fever in a baby under 3 months (100.4 degrees F or higher) - go to the ER
  • Fever above 104 degrees F that does not respond to medication at all
  • Fever with a stiff neck, severe headache, or persistent vomiting (possible meningitis)

My notes

From ismybabyalright.com — free, evidence-based baby health guides

All content follows our editorial policy and is reviewed against published clinical guidelines.

2,705 evidence-based guides6 authoritative medical sources5 medical advisory board members

Related Resources

Fever TriageWell-Baby Visit PrepMedicine Dosage CalculatorEmergency ContactsBaby Tracker

Bottom line

Most cases of baby has a high fever over 104 degrees f are normal. Talk to your pediatrician if any fever in a baby under 3 months (100.4 degrees f or higher) - go to the er.

Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.

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Fever in a Baby Under 3 Months Old

A fever in a baby under 3 months old (temperature of 100.4 degrees F / 38 degrees C or higher taken rectally) is always a medical emergency. Go to the emergency room immediately, regardless of how well your baby appears. Young babies' immune systems cannot fight infections as effectively as older children, and a fever could indicate a serious bacterial infection (urinary tract infection, bacteremia, or meningitis) that needs urgent treatment. Do NOT wait to see if the fever goes down. Do NOT give fever medication and stay home - go to the ER first.

Ibuprofen and Acetaminophen Dosing Safety

Acetaminophen (Tylenol) can be given to babies 2 months and older. Ibuprofen (Motrin/Advil) should NOT be given to babies under 6 months. Dosing is based on your child's WEIGHT, not age - always use the dosing syringe that comes with the product and follow the weight-based chart on the packaging. Never give aspirin to children under 18 (risk of Reye syndrome). When in doubt about dosing, call your pediatrician. Alternating acetaminophen and ibuprofen can be effective for fever but increases the risk of dosing errors - only do this under your pediatrician's guidance.

Cold vs. Flu in Baby - How to Tell the Difference

Colds and flu are both respiratory illnesses but are caused by different viruses and differ in severity. A cold comes on gradually with runny nose, sneezing, and mild cough. The flu hits suddenly with high fever, body aches, extreme fatigue, and a dry cough. Babies and children under 5 are at higher risk for flu complications. The flu can be treated with antiviral medication (like oseltamivir/Tamiflu) if started within 48 hours of symptom onset, which is why early evaluation is important. The best prevention is the annual flu vaccine, recommended for all children 6 months and older.

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