Fevers in children – what parents need to know
Medically reviewed by Dr. Betsy Koickel, MD on February 6th 2025.
As a parent, you often know immediately when your child has a fever. They have a glazed-over look and may be moving more slowly than normal. You check their temperature, and typically, you are right, they have a fever.
Fevers in children are relatively common and a sign that the body is fighting an infection. Most fevers can be managed at home with cooling measures, hydration, rest, or fever-reducing medications, but sometimes they may require medical attention.
Next time your child has a fever and isn’t feeling their best, here’s what you need to know to help them feel better and when you might want to seek additional help.
What is a fever?
A fever is an elevated body temperature typically caused by an illness or infection. What is considered a fever in children is defined as:
- 100.4°F (38°C) measured rectally (in the bottom), in the ear, or across the forehead
- 100°F (37.8°C) measured in the mouth
- 99°F (37.2°C) measured under the arm
These numbers are for children over the age of two. What is considered a fever is slightly different in children under two.
Common causes of fevers in children
Here are some common causes of fever in children:
- Bacterial infections (e.g., ear infections, strep throat)
- Immunizations
- Overheating or bundled up too warmly
- Teething (in younger children)
- Viral infections (e.g., colds, flu, RSV)
Symptoms to watch for - when to be concerned
Fevers can often be treated at home with hydration, rest, or over-the-counter medications. But they can sometimes be more serious and may require medical attention. Here are some warning signs of fever in children:
- Difficulty breathing or rapid breathing.
- High fever: Above 101°F for longer than 48 hours.
- Seizures: Febrile seizures can occur in some children with high fevers.
- Severe headache, neck stiffness, or rash.
- Signs of dehydration: Dry mouth, fewer wet diapers, lethargy.
- Unusual drowsiness, irritability, or difficulty waking up.
How to treat a fever at home
Many fevers can be treated at home. How can you reduce a fever in a child naturally? Keep them well hydrated, let them rest, or give them a cool washcloth. Use fever reducers like acetaminophen or ibuprofen if they’re uncomfortable.
Dress them in lightweight clothing and keep the room cool to help their bodies release heat. Always seek medical care if the fever is very high, lasts more than a couple of days, or if the child shows signs that may indicate a more severe illness.
Can a fever be dangerous?
Most fevers are not harmful long-term and can simply be part of the body’s natural immune response. If the fever is very high, over 104°F (40°C), this is when medical attention may be required.
When it lasts more than 2–3 days, or when it’s accompanied by red-flag symptoms mentioned above, it can be dangerous. Sometimes fevers can cause a seizure, which can be concerning, but they are usually treatable with medical care.
For infants under 3 months, any fever of 100.4°F (38°C) or higher requires immediate medical care. If a child is acting very ill, regardless of the fever they have, it’s safest to see a healthcare provider.
Preventing fevers in children
While all illnesses and fevers can’t be prevented, there are many lifestyle practices that can help reduce the risk of getting sick in both children and adults. These may include:
- Eating a well-balanced diet
- Getting enough sleep
- Keeping children away from sick contacts, when possible
- Maintaining good hand hygiene
- Staying up to date on vaccinations
When to visit urgent care for a fever
You should visit an urgent care for a fever when:
- Dehydration signs are present despite efforts to hydrate.
- Difficulty breathing, chest pain, or a rash develops.
- Fever lasts for more than 48 hours and is above 101°F.
- The child appears to be in severe discomfort, lethargic, or has difficulty waking up.
- You have pain with urination, abdominal pain, cough, or shortness of breath, and sore throat or rash
To get started, find the center near you and walk in or save your spot online.
FAQs about fevers on children
Here are frequently asked questions about fevers in children:
1. What is considered a fever in children?
A fever in children is typically a temperature of 100.4°F (38°C) or higher.
2. What are common causes of fever in children?
Common causes include viral infections, bacterial infections, vaccinations, overheating, and sometimes teething in very young children.
3. When should I be concerned about my child’s fever?
Be concerned if the fever reaches 104°F (40°C), lasts more than 2–3 days, or comes with symptoms like trouble breathing, severe lethargy, severe pain, or dehydration.
4. Should I use medication to reduce my child's fever?
You can use children’s fever medicine like acetaminophen or ibuprofen to reduce fever if your child is uncomfortable, but medication isn’t always necessary if they’re drinking, resting, and acting relatively normal.
5. How can I know when to seek help if I'm unsure about my child's fever?
If you’re unsure, seek help when the fever seems unusually high, your child appears very ill, or you have a gut feeling something isn’t right.
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