What to do when you think your child has a fever

fever child — What's considered normal for one type of thermometer may be different for another.
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Fever in children is common and is usually not an emergency.
However, if your child has a fever above 100.4 °F, or if your child is younger than 3 months and has any fever at all, you should get them medical aid.
You should also seek medical aid if your child has a fever and is experiencing symptoms including vomiting, diarrhea, confusion, and if the fever lasts for more than three consecutive days.
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Fever in children accounts for the majority of pediatrician and family physician consultations. It is most commonly caused by infections since body temperature increases when the immune system fights off bacteria and viruses.

A child’s temperature that exceeds 100.4 °F is considered a fever.

“For most children, having a fever is not an emergency and it’s not dangerous for a child to have a high temperature,” says Marina Masciale, MD, FAAP, Pediatric Hospitalist at Texas Children’s Hospital.

However, there are a couple of important caveats to Masciale’s advice:

If your child has a fever above 100.4 °F, then it’s considered a high fever and they need medical attention.
Call your health care provider immediately when an infant younger than 3 months develops even a mild fever.

Learn more about the causes and treatment of fever in children and when you should take your child to see a doctor.

How to take your child's temperature

A parent can take their child's temperature in several ways, including:

Temporal artery (forehead)
Oral (mouth)
Tympanic (ear)
Axillary (armpit)
Rectal (anus)

Different thermometers have different temperature ranges for what's considered normal. So always check the directions on the packaging for how to interpret an accurate reading. Here's a table of temperatures that indicate a high fever and should be given medical care:

Thermometer type	Children less than 3 months	Children older than 3 months
Temporal	>100.4 °F	>102.5 °F
Oral	N/A	>102 °F
Tympanic	>100.4 °F	>101.5 °F
Axillary	>100.4 °F	>101.5 °F
Rectal	>100.4 °F	>102.5 °F

Though parents and children dislike it, rectal thermometry is the most accurate way to measure core body temperature. "I recommend this method for children less than 3-4 months old because it's especially important to get an accurate temperature in this age group," says Masciale.

The accuracy of oral thermometry increases with age as children become more cooperative. Parents who don't have a thermometer may often check for fever by feeling the forehead with the back of their hand, but according to Masciale, this is not an accurate method.

Running around playing or dressing warmly may already increase body temperature, so evaluating through touch can overestimate the presence of fever. To be completely certain, use a thermometer, and if you're fresh out check for other symptoms that may indicate the presence of an infection.

What causes fever in children?

A fever is a body's way of fighting infection. At a higher temperature, some parts of the immune system work better and some bacteria and viruses replicate less, says Lauren M. Hess, MD, FAAP, Assistant Professor of Pediatrics at Baylor College of Medicine.

Many common conditions can cause a fever, but most come from viral infections, such as:

Common cold: A fever will be mild and can be accompanied by cough, hoarseness, and nasal discharge.
Chickenpox: Aside from the distinctive chickenpox rash, symptoms also include loss of appetite, headache, and tiredness.
Roseola: In some cases, symptoms like rashes and swollen eyelids are too mild to be easily recognized.
Flu: Other than the fever, the child may also experience vomiting, diarrhea, and fatigue.

Some of the common causes of fever in children come from bacterial infections as well, which includes:

Urinary tract infections (UTIs): An unexplained fever might be the only evident symptom of UTI in children up to two years old. Specific signs like dysuria, cloudy urine, and a more frequent need to urinate appear after the age of two.
Strep throat: The symptoms include sore throat, painful swallowing, abdominal pain, headache, and sometimes nausea.
Acute otitis media (AOM) or a middle ear infection: Fever with ear pain, difficulty sleeping, and constant ear tugging may indicate an ear infection.
Conjunctivitis or pink eye: Pink eye can be caused by a viral or bacterial infection. The infection is usually characterized by redness, itchiness, discharge, and possible tearing in one or both eyes.

The less common causes of fever are dehydration, teething, or sunburn. In rare cases, pneumonia, metabolic diseases, and allergic reactions to food or medications can also result in a fever.

"Fever is just a symptom and actually one way your child's body is working to cure itself," says Hess. "Treat your child and not the temperature."

In about 10%-30% of cases of fever, the cause cannot be conclusively determined.

Treating your child's fever

There are different treatment options to reduce a child's fever. Experts recommend that feverish children drink plenty of fluids because they get dehydrated more easily. Wearing lightweight clothing can also have a cooling effect.

Parents may give their child some over-the-counter medications to relieve their symptoms, such as:

Tylenol: Acetaminophen, the active ingredient in Tylenol, reduces fever, sore throat, aches, and pain. It is only for children above two years old unless otherwise cleared by the doctor.
Advil or Motrin: Ibuprofen relieves headaches and reduces fever, sore throat, aches, and pain. Do not give ibuprofen to children younger than 6 months.

Common home remedies, like dabbing a damp cloth on the child, is not proven to reduce fever, but it can still help make them more comfortable.

However, Hess says to avoid cold baths because, "this will induce the body to start shivering as the brain fights to bring the temperature back up," says Hess. And shivering can actually ramp up a fever even more, worsening symptoms.

When to see a doctor

Fevers in children usually go away within a week or less. However, Masciale says that a child is at risk of getting infected by more serious bacteria if they haven't received their standard vaccinations. There's also the risk of a secondary infection. For example, the flu can cause secondary infections like pneumonia or encephalitis.

According to her, you should call your healthcare provider and discuss scheduling an appointment if your child is experiencing the following symptoms:

Vomiting
Diarrhea
Confusion
Severe pain in the body
Febrile seizures, or convulsions triggered by fever
A fever that exceeds three days
A persistent fever that comes and goes
Showing signs of dehydration like urinating less often, having a dry mouth, or having no tears when crying

"It's important to get checked out by a doctor to make sure there isn't something more serious going on that their body cannot fight off on its own," says Masciale.

Experts recommend going straight to the emergency room (ER) if the child is struggling to breathe, not waking up, or if they are younger than 3 months.

"Depending on the situation, the doctor will likely take a full set of vital signs, talk to you, and examine your child," says Hess. "But know that the moment your child gets to the ER, they are triaged."

Insider's takeaway

If you're worried that your child may have a fever, the most conclusive way to know for sure is by measuring their temperature using a thermometer.

Bacterial and viral infections often cause fevers in children, so discuss treatment options with a healthcare provider. If their symptoms worsen, see a doctor immediately.

"In most cases, the height of the fever isn't important," says Hess. The fever duration and clinical condition is more crucial in assessing illness severity.