Fever (also called pyrexia) is defined as body temperature that is higher than normal for each individual. It generally indicates that there is an abnormal process occurring in the body. Exercise, hot weather, and common childhood immunizations can also make body temperature rise.
Fever is not an illness, but, rather, a symptom or an indicator that something is not right within the body. A fever does not tell you what disorder is causing it, or even that a disease process is occurring. It may be a bacterial or viral infection, or simply a reaction from an allergy to food or medication, or becoming overheated at play or in the sun.
Although high fevers may bring on convulsions or delirium, generally, it is not how high the temperature is, but how rapidly the temperature rose that causes a convulsion.
If symptoms of an illness are present:
A temperature between 99.8° F-100.8° F is considered a low-grade fever.
A temperature between 101° F-102° F is considered a mild fever.
A temperature between 102° F-103° F is considered a moderate fever.
A temperature around 104° F or above is considered a high fever, and delirium or convulsions may occur.
Your physician may have different definitions of fever than these, and will provide guidelines for when to treat fever yourself and when to call the physician's office.
Because a baby, young child, or disabled person may not be able to express how he or she is feeling, be sure to look for signs (outward indications) that fever is present before using a thermometer. Signs that indicate fever may include the following:
Hot, dry skin
Low output of urine, and/or dark urine
Not interested in eating
Constipation or diarrhea
Aching all over
The best means of taking temperature is with a thermometer. There are several types of thermometers, including the following:
Glass thermometers (oral or rectal)
Taking a temperature reading with a thermometer directly touching certain areas of the skin, such as under the arm or in the bend of the elbow, is not recommended because it is not considered to be reliable.
According to the Environmental Protection Agency, mercury is a toxic substance that poses a threat to the health of humans, as well as to the environment. Because of the risk of breaking, glass thermometers containing mercury should be removed from use and disposed of properly in accordance with local, state, and federal laws. Contact your local health department, waste disposal authority, or fire department for information on how to properly dispose of mercury thermometers.
Once you have determined that the person has a fever, you may treat it by giving acetaminophen (Tylenol®, Tempra®, or FeverAll®) or ibuprofen (Advil® or Motrin®), or both, in dosages or combinations advised by your physician. Never give aspirin to a child or young adult who has a fever.
A tepid bath (water is neither too cool nor too warm to the touch) may reduce the fever, as well as comfort the person. Alcohol rubdowns are no longer recommended.
Call your physician for guidance anytime you are uncomfortable with the conditions of the fever, and remember to contact your physician anytime a temperature spikes rapidly or persists despite treatment.
Call your physician immediately if any of the following conditions accompany a fever:
Feeling dull or sleepy
Purple spotted rash
Ear pain (a child tugging on his/her ear)
Sore throat that persists
Painful, burning, or frequent urination
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