This information is approved and/or reviewed by U-M Health System providers but it is not a tool for self-diagnosis or a substitute for medical treatment. You should speak to your physician or make an appointment to be seen if you have questions or concerns about this information or your medical condition. Exención de responsabilidad en Español | Complete disclaimer
Misconceptions about the dangers of fever are commonplace. Unwarranted fears about harmful side effects from fever cause lost sleep and unnecessary stress for many parents. Let the following facts help you put fever into perspective:
MYTH: All fevers are bad for children.
FACT: Fevers turn on the body's immune system. Fevers are one of the body's protective mechanisms.
Most fevers are good for sick children and help the body fight infection. The exception is babies less than 3 months of age. They should be seen by a healthcare provider right away. Use the following definitions to help put your child's level of fever into perspective:
100°F to 102°F Low-grade fever: Beneficial. Try
(37.8°C to 39°C) to keep the fever in this range.
102°F to 104°F Moderate-grade fever: Beneficial.
(39°C to 40°C)
Over 104°F High fever: Causes discomfort, but
(40°C) is harmless.
Over 105°F High fever: Higher risk of
(40.6°C) bacterial infections.
Over 108°F Serious fever: The fever itself can
(42°C) be harmful.
MYTH: Fevers cause brain damage or fevers over 104°F (40°C) are dangerous.
FACT: Fevers with infections don't cause brain damage. Only body temperatures over 108°F (42°C) can cause brain damage. The body temperature goes this high only with extreme environmental temperatures (for example, if a child is confined in a closed car in hot weather).
MYTH: Anyone can have a febrile seizure (seizure triggered by fever).
FACT: Only 4% of children have a febrile seizures.
MYTH: Febrile seizures are harmful.
FACT: Febrile seizures are scary to watch, but they usually stop within 5 minutes. They cause no permanent harm. Children who have had febrile seizures do not have a greater risk for developmental delays, learning disabilities, or seizures without fever.
MYTH: All fevers need to be treated with fever medicine.
FACT: Fevers need to be treated only if they cause discomfort. Usually that means fevers over 102°F or 103°F (39°C or 39.4°C).
MYTH: Without treatment, fevers will keep going higher.
FACT: Wrong. Because of the brain's thermostat, fevers from infection top out at 103°F to 104°F (39.4°C to 40°C). They rarely go to 105°F or 106°F (40.6°C or 41.1°C).
MYTH: With treatment, fevers should come down to normal.
FACT: With treatment, fevers usually come down 2° or 3°F (1.1° or 1.7°C).
MYTH: If the fever doesn't come down (if you can't "break the fever"), the cause is serious.
FACT: Fevers that don't respond to fever medicine can be caused by viruses or bacteria. Whether the medicine works or not doesn't relate to the seriousness of the infection.
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 is what's important, not the exact temperature.
MYTH: Temperatures between 98.7°F and 100°F (37.1°C to 37.8°C) are low-grade fevers.
FACT: These temperatures are normal variations. The normal temperature changes throughout the day. It peaks in the late afternoon and evening. A low-grade fever is 100°F to 102°F (37.8°C to 39°C).
MYTH: Feed a cold, starve a fever.
FACT: This old saying should be ignored. Fevers cause the body to lose fluids through sweating and breathing. Children with fevers need lots of fluids. Children with a fever may or may not be hungry for food. If they are hungry, offer the food that they choose. It is helpful to do so.
