Overview
Fever is one of the most common reasons parents bring their children to the doctor. While fever can be scary, it's usually a sign that your child's body is fighting an infection. Most fevers are caused by viruses and will go away on their own. However, it's important to know when fever needs medical attention.
Why this matters for your child
What is a fever?
A fever is a temperature of 100.4°F (38°C) or higher. The most accurate way to measure depends on your child's age: for babies under 3 months, use a digital thermometer rectally; for children 1 year and older, an ear thermometer or a digital thermometer under the arm works well.
How your child looks matters more than the number
A child with a high fever who is still playing and drinking is usually less concerning than a child with a lower fever who is very sleepy and won't drink. Trust what you see, not just the thermometer.
Common symptoms
Along with a higher temperature, you may notice:
- Chills or shivering
- Sweating
- Fussiness or irritability
- Decreased appetite
- Decreased activity or more sleepiness
- Headache
When to see a doctor
Contact your child's doctor promptly if any of the following apply. Mercer Island Pediatrics has nurses and a physician on call 24/7 to discuss your concerns.
Age-related concerns
- Your baby is younger than 3 months old with ANY fever
- Your baby is 3 months to 3 years old with a fever of 102.2°F (39°C) or higher
Behavioral changes
- Unusually sleepy or hard to wake
- Not drinking fluids or showing signs of dehydration (dry mouth, no tears, fewer wet diapers)
- Won't eat or drink anything
- Very fussy or irritable and difficult to comfort
- Not acting like themselves
Other concerning signs
- Fever lasts more than 3 days
- Fever goes away for more than 24 hours and then comes back
- Pain with urination or foul-smelling urine
- Persistent vomiting or diarrhea
- You're worried something is seriously wrong — trust your instincts
Seek immediate care
Call 911 or go to the emergency room right away if your child has fever AND any of these warning signs:
- Blue or purple skin color, especially around the lips
- Tiny red or purple spots on the skin that don't fade when you press on them
- Extreme difficulty breathing or grunting sounds
- Limp, floppy, or won't move
- Won't wake up or extremely difficult to wake
- Inconsolable crying that won't stop
- Stiff neck or severe headache
- Seizure or convulsion
Treatment & management options
Most fevers can be managed at home. If your child is drinking fluids well, playful and interactive when the fever comes down, and breathing normally, home care is usually appropriate. Not every fever needs medication — only treat if your child is in pain or uncomfortable. Keeping your child hydrated is one of the most important things you can do.
Hydration
For babies, offer breastfeeding or formula more often. For older children, popsicles, Gatorade, Pedialyte, and diluted juice are all good options.
If you choose to give medicine
- Acetaminophen (Tylenol): can be used in children of all ages. Dose by weight, not age. Do not give more than 4 times in 24 hours.
- Ibuprofen (Advil, Motrin): for children 6 months and older. Dose by weight. May be given every 6–8 hours.
- Never give aspirin to children.
Other comfort measures
- Dress your child in light, comfortable clothing (one layer)
- Keep the room at a comfortable temperature — not too hot or cold
- Offer plenty of fluids: water, breast milk, formula, or diluted juice
- Let your child rest as much as they want
- Do NOT use cold baths, ice baths, or alcohol rubs — these can be dangerous
Reassurance for parents
Mercer Island Pediatrics is here for you. We always have same-day appointments for urgent sick visits and we're open on Saturday mornings. We can evaluate your child in the office and decide whether further imaging or labs are needed based on symptoms and exam. Most fevers just need to be monitored — the most common cause is a virus.
Ready to talk?
When in doubt, trust your instincts. You know your child best. If something doesn't seem right, call us.
This guide is for general education only. When in doubt, call us — we'd rather hear from you.