Serving all people by providing personalized health and wellness through exemplary care, education and research.
Explore health content from A to Z.
I need information about...
Return to Index
Fever is the only symptom
Fever can be defined using one of the following measurements:
Oral temperature greater than 100.0° F (37.8° C)
Ear (tympanic) temperature greater than 100.4° F (38.0°C)
Rectal temperature greater than 100.4°F (38.0°C)
Forehead temperature strips are unreliable
In most clinical situations, fever does no major harm, and may actually benefit the human body by helping it to fight off infection. Nevertheless, fever is an abnormal finding. It can signal a serious illness, especially in adults who are old, frail, or have a weakened immune system.
Adults tend to run lower fevers than children. Fever may be further blunted or even absent in elderly patients.
Fever itself can cause muscle aches, nausea, lightheadedness, weakness and headache.
Normal Body Temperature
98.6° F (37°C) is the oral temperature that most physicians, nurses, laypersons, and medical references state is "normal."
The average temperature of healthy elderly patients is the same as younger adults. However, there is some data to suggest that the average temperature in chronically ill elderly patients is lower than that of other healthy adults. Thus, interpretation of a temperature reading in a chronically ill elderly adult must be done with caution. Because lower baseline temperatures can be expected in this group of patients, it may be easy to miss a fever if the conventional fever definition is used.
Normal Variations in Body Temperature
There is a normal daily awake-sleep cycle variation in temperature, with the low occurring at 6 AM and the high occurring at 6 PM. The low and high temperatures vary by 0.9° F (0.6° C).
In women, temperature increases about 0.9° F (0.6° C) at the time of ovulation.
Temperature can go up in response to physical activity, particularly during hot weather.
Any other symptom is present with the fever (See that topic; e.g., COLDS, COUGH, SORE THROAT, EARACHE, DIARRHEA, VOMITING, etc.)
FIRST AID Advice for Shock: Lie down with the feet elevated.
Difficult to awaken or acting confused
Very weak (can't stand)
Severe difficulty breathing (e.g., struggling for each breath, unable to speak)
Lips or face are blue
Rash with purple (blood-colored) spots or dots
You feel weak or very sick
Fever of 103° F (39.4° C) or higher
Fever of 100.5° F (38.1° C) or higher and you:
Are over 60 years of age OR
Have diabetes mellitus or a weakened immune system (e.g., HIV positive, cancer chemotherapy, chronic steroid treatment, splenectomy) OR
Are bedridden (e.g., nursing home patient, stroke, chronic illness, recovering from surgery) OR
Are a transplant patient (e.g., liver, heart, lung, kidney)
Headache and stiff neck (can't touch chin to chest)
Signs of dehydration (e.g., no urine in more than 12 hours, very dry mouth, lightheaded, etc.)
Have an intravenous catheter (e.g., central line, PICC, or peripheral intravenous line)
You think you need to be seen
Fever of 100.5° F (38.1° C) or higher and you have traveled to a foreign country in the last month
Fever present for more than 3 days
You have other questions or concerns
Fever with no signs of serious infection and you don't think you need to be seen
Reassurance: The presence of a fever usually means that you have an infection. Most fevers are good and help the body fight infection. The goal of fever therapy is to bring the fever down to a comfortable level. Use the following definitions to help put the level of fever into proper perspective:
100-102° F (37.8 - 38.9° C): Low-grade fevers and may help body fight infection.
102-104° F (38.9 - 40° C): Moderate-grade fevers; cause discomfort.
Over 104° F (over 40° C): High fevers; cause discomfort, weakness, headache, lethargy.
Over 107° F (over 41.7° C): The fever itself can be harmful.
For All Fevers:
Drink cold fluids orally to prevent dehydration (Reason: good hydration replaces sweat and improves heat loss via skin). Adults should drink 6-8 glasses of water daily.
Dress in one layer of lightweight clothing and sleep with one light blanket.
For fevers 100-101° F (37.8-38.3° C), this is the only treatment and fever medicine is unnecessary.
For fevers above 101° F (38.3° C) take acetaminophen or ibuprofen.
The goal of fever therapy is to bring the fever down to a comfortable level. Remember that fever medicine usually lowers fever 2 degrees F (1 - 1 1/2 degrees C).
Acetaminophen (e.g., Tylenol):
Take 650 mg by mouth every 4-6 hours. Each Regular Strength Tylenol pill has 325 mg of acetaminophen.
Another choice is to take 1,000 mg every 8 hours. Each Extra Strength Tylenol pill has 500 mg of acetaminophen.
The most you should take each day is 3,000 mg.
Ibuprofen (e.g., Motrin, Advil):
Take 400 mg by mouth every 6 hours.
Another choice is to take 600 mg by mouth every 8 hours.
Use the lowest amount that makes your pain feel better.
Acetaminophen is thought to be safer than ibuprofen in people over 65 years old. Acetaminophen is in many OTC and prescription medicines. It might be in more than one medicine that you are taking. You need to be careful and not take an overdose. An acetaminophen overdose can hurt the liver.
CAUTION: Do not take acetaminophen if you have liver disease.
CAUTION: Do not take ibuprofen if you have stomach problems, kidney disease, are pregnant, or have been told by your doctor to avoid this type of anti-inflammatory drug. Do not take ibuprofen for more than 7 days without consulting your doctor.
Before taking any medicine, read all the instructions on the package.
Lukewarm Shower for Reducing Fever: Take the fever medicine first. Take a lukewarm shower or bath for 10 minutes. Lukewarm water should be warm enough that it does not make you shiver, but cold enough that it helps cool you off and reduce your temperature. Do not sponge yourself with rubbing alcohol.
Expected Course: Most fevers from a viral illness such as a cold fluctuate between 99.5 and 103° F (37.5 - 39.5° C) and last for 2 or 3 days.
Contagiousness: You can return to work or school after the fever is gone.
Call Your Doctor If:
Fever lasts longer than 3 days (72 hours)
You become worse
Copyright © 2015 Baylor Scott & White Health. All Rights Reserved. |
3500 Gaston Avenue, Dallas, TX 75246-2017 | 1.800.4BAYLOR