Many parents have false beliefs (myths) about fever. They think fever will hurt their child. They worry and lose sleep when their child has a fever. This is called fever phobia. In fact, fevers are harmless and often helpful. Let these facts help you better understand fever.

MYTH. My child feels warm, so she has a fever.

FACT. Children can feel warm for a many reasons. Examples are playing hard, crying, getting out of a warm bed or hot weather. They are “giving off heat.” Their skin temperature should return to normal in about 20 minutes. About 80% of children who act sick and feel warm do have a fever. If you want to be sure, take the temperature. These are the cutoffs for fever using different types of thermometers:

• Rectal (bottom), ear or forehead temperature: 100.4° F (38.0° C) or higher
• Oral (mouth) temperature: 100° F (37.8° C) or higher
• Under the arm (Armpit) temperature: 99° F (37.2° C) or higher

MYTH. All fevers are bad for children.

FACT. Fevers turn on the body’s immune system. They help the body fight infection. Normal fevers between 100° and 104° F (37.8° – 40° C) are good for sick children.

MYTH. Fevers above 104° F (40° C) are dangerous. They can cause brain damage.

FACT. Fevers with infections don’t cause brain damage. Only temperatures above 108° F (42° C) can cause brain damage. It’s very rare for the body temperature to climb this high. It only happens if the air temperature is very high. An example is a child left in a closed car during hot weather.

MYTH. Anyone can have a seizure triggered by fever.

FACT. Only 4% of children can have a seizure with fever.

MYTH. Seizures with fever are harmful.

FACT. These seizures are scary to watch, but they stop within 5 minutes. They don’t cause any permanent harm. They don’t increase the risk for speech delays, learning problems, or seizures without fever.

MYTH. All fevers need to be treated with fever medicine.

FACT. Fevers only need to be treated if they cause discomfort (makes your child feel bad). Most fevers don’t cause discomfort until they go above 102° or 103° F (39° or 39.5° C).

MYTH. Without treatment, fevers will keep going higher.

FACT. Wrong, because the brain knows when the body is too hot. Most fevers from infection don’t go above 103° or 104° F (39.5°- 40° C). They rarely go to 105° or 106° F (40.6° or 41.1° C). While these are “high” fevers, they also are harmless ones.

MYTH. With treatment, fevers should come down to normal.

FACT. With treatment, most fevers come down 2° or 3° F (1° or 1.5° C).

MYTH. If you can’t “break the fever”, the cause is serious.

FACT. Fevers that don’t come down to normal can be caused by viruses or bacteria. The response to fever medicines tells us nothing about the cause of the infection.

MYTH. Once the fever comes down with medicines, it should stay down.

FACT. It’s normal for fevers with most viral infections to last for 2 or 3 days. When the fever medicine wears off, the fever will come back. It may need to be treated again. The fever will go away and not return once the body overpowers the virus. Most often, this is day 3 or 4.

MYTH. If the fever is high, the cause is serious.

FACT. If the fever is high, the cause may or may not be serious. If your child looks very sick, the cause is more likely to be serious.

MYTH. The exact number of the temperature is very important.

FACT. How your child looks and acts is what’s important. The exact temperature number is not.

MYTH. Oral temperatures between 98.7° and 100° F (37.1° to 37.8° C) are low-grade fevers.

FACT. These temperatures are normal. The body’s normal temperature changes throughout the day. It peaks in the late afternoon and evening. A true low-grade fever is 100° F to 102° F (37.8° – 39° C) .

SUMMARY. Keep in mind that fever is fighting off your child’s infection. Fever is one of the good guys.

Barton Schmitt MD, FAAP

Copyright 2000-2022 Schmitt Pediatric Guidelines LLC.