September 26, 2022

Fever in Babies and Children: When To Worry

Behavior and age are important clues

mom taking sick child's temperature

Your knee-jerk reaction when your child develops a fever may be to immediately start ringing the alarms. Fevers can be scary for parents, especially first-timers. You might wonder how high is too high or if you should call the doctor immediately if your child has one. Certainly, something must be done, right?

Advertisement

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

Well, not always. It turns out that not all fevers are something to fret about. And knowing the difference between a fever that needs treatment and a fever that can be left to run its course can help your child get better faster — and with less stress on you.

“Every child will eventually experience a fever, no matter how careful you are,” says pediatrician Tracy Lim, MD. And it’s important for parents to know what to do when this happens.

We talked with Dr. Lim about how to spot a worrisome fever in children and what to do when your child has a fever.

Tips on taking your child’s temperature

First thing first. To know if your child is running a fever, you’ll need to take their temperature. But a look at online stores or a trip down the pharmacy aisle can leave you wondering which of those thermometer gadgets you actually need.

There’s a wide variety of thermometers available, from standard oral thermometers to temporal artery scanners.

“It is most accurate to use a rectal thermometer for infants and young children, but if you feel uneasy doing this, use whichever device makes you most comfortable,” Dr. Lim says. “In older children, an oral temperature is most accurate, if the child is able to tolerate it.”

What’s considered a fever?

A “normal” body temperature is 98.6 degrees Fahrenheit, or 37 degrees Celsius, but that doesn’t mean you have to hit the panic button if your child’s temperature inches above that. Everyone’s temperature will vary a little throughout the day. It can also differ by age, activity level and other factors.

The type of thermometer you use will change the definition of what’s actually a fever for your child. Different kinds of thermometers have different levels of accuracy. This fever chart can help you understand the results you’re seeing.

Advertisement

Child fever temperature chart

Child’s age
0 to 2 years
Best type of thermometer
Rectal
What’s considered a fever?
100.4 F (38 C)
0 to 2 years
Best type of thermometer
Armpit
What’s considered a fever?
99 F (37.22 C)
2 to 5 years
Best type of thermometer
Rectal
What’s considered a fever?
100.4 F (38 C)
2 to 5 years
Best type of thermometer
Ear
What’s considered a fever?
100.4 F (38 C)
2 to 5 years
Best type of thermometer
Armpit
What’s considered a fever?
99 F (37.22 C)
5+ years
Best type of thermometer
Ear
What’s considered a fever?
100.4 F (38 C)
5+ years
Best type of thermometer
Mouth
What’s considered a fever?
100 F (37.77 C)
5+ years
Best type of thermometer
Armpit
What’s considered a fever?
99 F (37.22 C)

Some fevers are OK

It can be worrying to see your kid spike even a mild fever. We get it. But the truth is that a fever is actually a sign that your child is fighting off germs. It’s doing what it’s supposed to. And that’s a good thing.

When should you not worry about your child’s fever?

Dr. Lim says doctors tend not to worry about a fever if it’s mild, lasts fewer than five days and doesn’t affect your kid’s day-to-day activities.

The following fevers can be monitored at home. If needed, you can also treat them with:

  • Fever-reducing medication such as infant or children’s acetaminophen (Tylenol®).
  • Cool compresses.
  • Plenty of liquids to prevent dehydration.
  • Rest.

A temperature below a certain threshold

In a child over 4 months, fevers of up to 104 F shouldn’t cause alarm. A mild fever that lasts up to five days is OK for most kids.

A fever that doesn’t affect your child too much

If your child’s behavior is relatively normal, you don’t need to be concerned. Monitor them and see if they continue to be playful and if they’re eating and drinking normally. A child with a fever may seem more tired than usual, but if they’re otherwise acting normal, there’s no reason to worry.

When to call a doctor for a fever

Now for the important question: When should you be worried about a fever? Call your doctor in these cases.

Fevers in infants under 3 months

Fevers may be your infant’s only response to a serious illness. Especially in newborns, a low temperature can also be a sign of serious illness. Call a healthcare provider if your baby has any fever or if their temperature drops below 97.7 F (36.5 C) rectally.

Advertisement

High fever in infants and children over 3 months

In babies and children over 3 months, call a healthcare provider if your child’s fever is higher than 104 F (40 C), or if the fever doesn’t come down with a fever-reducing medication.

Your child’s fever lasts more than five days

Your pediatrician may need to investigate further for underlying causes.

Your child’s fever doesn’t come down with fever reducers

Infant and children’s versions of medications like acetaminophen can be used at home in babies and children if OK’d by their healthcare provider. The medications should work quickly to reduce your child’s fever. Contact a doctor if your child’s fever continues even after using a fever-reducing medication.

Your child isn’t acting like themselves

If your child shows these signs of illness, it’s time to call a healthcare provider:

  • Difficult to arouse.
  • Not taking in enough liquids.
  • Babies who aren’t wetting at least four diapers per day.
  • Older children who aren’t urinating every eight to 12 hours.

You’re concerned

Sometimes, parents’ instincts are meaningful. If you’re uncomfortable with your child’s temperature or illness, call a healthcare provider to discuss it.

Can fever cause a seizure?

Seizures can be a very scary side effect of fevers in some children. Febrile seizures occur in 2% to 4% of all children under age 5. Not all seizures cause jerking movements in the body. Dr. Lim says some seizures look like “passing out.” If your child develops a seizure:

  • Put your child on their side.
  • Do NOT put anything in your child’s mouth.
  • Call 911 if the seizure lasts more than five minutes.

If the seizure lasts fewer than five minutes, call your physician or seek immediate medical attention.

Related Articles

Child in bed sick with parent's hand in foreground holding thermometer.
September 10, 2023
Too Sick for School? How To Decide if You Should Keep Your Kid Home

Vomiting and fevers are a hard no — other symptoms are a judgment call

Parent checking temperature of small sickly child in bed.
June 20, 2023
Scarlet Fever and Strep Have Been on the Rise: What Should You Know — and Do — About It?

Awareness and prompt treatment can help keep your family safe

person blowing their nose outside
May 16, 2023
Allergies Don’t Cause a Fever — At Least, Not Directly

Infections like sinusitis, colds, flu and COVID-19 can cause a fever, but allergies aren’t infections

Teething baby crying
April 30, 2023
Teething Doesn’t Cause Fevers — and Other Myths To Sink Your Teeth Into

Drooling, chewing and mild fussing are the most common baby teething symptoms

Child with fever has wet washcloth on forehead.
April 26, 2023
Never Use Rubbing Alcohol To Bring Down a Fever

It can cause alcohol poisoning and other serious health issues, especially in kids

parent caring for child's fever in bed
April 16, 2023
How To Treat Your Child’s Fever Naturally (and When To Let It Run Its Course)

It’s important not to give them fever-reducing medications right off the bat

checking temperature with a digital thermometer
February 20, 2023
What Is a Normal Body Temperature?

There’s no one answer, as your temperature fluctuates throughout the day and your life

Someone cooking chicken noodle soup.
February 1, 2023
Fact or Fiction: Feed a Cold, Starve a Fever

The advice dates to 1574, but it doesn’t quite meet modern medical guidelines

Trending Topics

White bowls full of pumpkin seeds, dark chocolate and various kinds of nuts
25 Magnesium-Rich Foods You Should Be Eating

A healthy diet can easily meet your body’s important demands for magnesium

Woman feeling for heart rate in neck on run outside, smartwatch and earbuds
Heart Rate Zones Explained

A super high heart rate means you’re burning more than fat

Spoonful of farro salad with tomato
What To Eat If You’ve Been Diagnosed With Prediabetes

Type 2 diabetes isn’t inevitable with these dietary changes

Ad