Newborn (0–2 months) · Infant (2–12 months) · Toddler (1–3 years) · Preschool (3–5 years) · School age (5–12 years) · Illness & symptoms
Fever in babies and children: what to do and when to call
A fever is a temperature of 100.4°F (38°C) or higher. In a baby under 3 months it is an emergency; in older children it is usually the body fighting an infection, and comfort matters more than the number.
Key takeaways
- 100.4°F (38°C) or higher is a fever, measured rectally in babies
- Under 3 months with a fever: call us or go to the ER right away
- Over 3 months: treat discomfort, not the number; fluids and rest
- Dose acetaminophen or ibuprofen by weight, never by age
- Call for fever over 3 days, a fever with a rash, or a child who is hard to wake
Is a fever dangerous?
Usually not. Fever is a sign the immune system is working. Most fevers from viruses last two to three days and cause no harm. What matters is how your child looks and acts: a child who drinks, plays a little and comforts easily is doing fine even at 103°F.
How should I take the temperature?
Rectal thermometers are most accurate for babies under 3 months. Forehead (temporal) and ear thermometers are fine for older children; ear readings are unreliable under 6 months. Skip strip thermometers.
What can I give?
Acetaminophen (Tylenol) for any age over 3 months with our okay, and ibuprofen (Motrin, Advil) from 6 months. Dose by your child’s weight using the AAP dosing tables. Do not use aspirin. Alternating medicines is rarely needed and easy to get wrong; pick one.
What else helps?
- Offer fluids often: breast milk, formula, water or an electrolyte drink
- Dress lightly; skip the cold bath, which causes shivering
- Let them rest, but do not force sleep
- Keep them home from school or daycare until fever-free for 24 hours without medicine
When to call us
- Fever lasting more than 3 days
- Fever with a new rash, ear pain, sore throat, or painful urination
- Fewer wet diapers, no tears, or a dry mouth
- Your child is unusually sleepy, fussy, or not drinking
- Fever returns after going away for a day or more
Go to the emergency room or call 911 if…
- Any fever in a baby under 3 months (rectal 100.4°F or higher)
- Trouble breathing, blue lips, or a stiff neck
- A seizure, or a child who is very hard to wake
- A purple, non-blanching rash
- Fever over 105°F that does not come down
Questions parents ask
Should I wake my child to give fever medicine?
No. Sleep is more useful than a lower number. Give medicine when they wake if they are uncomfortable.
Can teething cause a fever?
Teething can raise the temperature slightly but does not cause a true fever of 100.4°F or higher. A fever means something else is going on.
Not sure? Ask us
Call or text the office during hours, or send a portal message. For emergencies call 911.
(770) 615-7000Trusted further reading
- Acetaminophen dosing table (opens in new tab)HealthyChildren.org (AAP)
- Ibuprofen dosing table (opens in new tab)HealthyChildren.org (AAP)