Fever is a higher-than-normal body temperature. The ‘normal’ temperature varies from person to person, varies depending on how it is measured (oral, axillary, rectal, tympanic, or core), and varies between morning and afternoon. Usually, an oral temperature around 98.6° Fahrenheit (F) or 37° Celsius (C) is considered normal. A rise in temperature of 101 ° F generally is considered a fever. Fever is not a disease, but can be a symptom of illness.
- Exercise, dehydration, or warm room temperatures can cause the body temperature to rise; this is not a true fever.
- Fever is most commonly caused by infection.
- Certain non-infectious illnesses can cause fever.
- An allergic reaction to some medications can cause a fever.
- Occasionally, the source of a fever cannot be determined (called, "fever of unknown origin").
The signs and symptoms of a fever depend on the cause. At first, a fever can cause a chill. When the brain raises the body's "thermostat," the body responds by shivering. Shivering produces heat, and this raises the body's temperature. Once the body temperature rises, the person often feels warm. After a time, the brain’s signal for fever goes away, and the ‘thermostat’ resets. The person may sweat as a way of giving off heat and cooling down.
The temperature can be taken in the mouth, rectum, ear, or under the arm by use of a thermometer. There are many different types of thermometers. The temperature considered a fever varies with type of measurement (and, technically, time of day). An oral temperature of around 101° F or 38.5° C is a fever.
- Acetaminophen or ibuprofen may be used to control temperature.
- Do not give aspirin to children with fevers. There is an association with Reye's syndrome.
- If an infection is present and medications have been prescribed, take them as directed. Finish the full course of medications until they are gone.
- Sponging or bathing in lukewarm water can cool the skin and reduce body temperature. Do not use ice water or alcohol sponge baths as they may cause shivering and actually may raise the body temperature.
- Do not over-bundle children in blankets or heavy clothes.
- Drinking adequate fluids during an illness with fever is important to prevent dehydration.
SEEK MEDICAL CARE IF:
- You or your child are unable to keep fluids down.
- Vomiting or diarrhea become persistent.
- A fever persists for over 3 days.
- You or your child develop excessive weakness, dizziness, fainting or extreme thirst.
- Fevers greater than 106° F (41° C) develop. These are serious and should be evaluated by your caregiver or in a hospital.