Fever is considered a temperature above 100.4 degrees F (38 degrees C). A feverish sensation, however, may occur when the body temperature is above the average normal of 98.6 degrees F. (37 degrees C).

Fever is part of the body's own disease-fighting arsenal. Rising body temperatures apparently are capable of killing off many disease-producing organisms. For that reason, low fevers should normally go untreated. Although, if the fever is accompanied by any other troubling symptoms, you may need to see your doctor to be certain. As fevers range to 104 F and above, however, there can be unwanted consequences, particularly for children. These can include delirium and convulsions. A fever of this sort demands immediate home treatment and then medical attention. Home treatment possibilities include the use of aspirin or, in children, nonaspirin painkillers such as acetaminophen (Tylenol), cool baths, or sponging to reduce the fever while seeking medical help. Fever may occur with almost any type of infection of illness. The temperature is measured with a thermometer.

Fever is also called pyrexia.

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