Normal body temperatures vary depending on many factors, including
- age,
- sex,
- time of day,
- ambient temperature,
- activity level, and more.
A raised temperature is not always a fever. For example, the temperature of a healthy person rises when he or she exercises, but this is not considered a fever, as the set point is normal. On the other hand, a “normal” temperature may be a fever, if it is unusually high for that person. For example, medically frail elderly people have a decreased ability to generate body heat, so a “normal” temperature of 37.3 °C (99.1 °F) may represent a clinically significant fever.
Temperature rise different body parts:
Your body creates a fever by Definitions of fever vary, but are generally accepted to be:
- Rectal temperature above 100.4ºF (38ºC)
- Oral temperature above 100ºF (37.8ºC)
- Axillary (armpit) temperature above 99ºF (37.2ºC)
- Ear (tympanic membrane) temperature above 100.4ºF (38ºC) in rectal mode or 99.5ºF (37.5ºC) in oral mode
- Forehead (temporal artery) temperature above 100.4ºF (38ºC).
Taking a temperature:
To check your or your child’s temperature, you can choose from several types of thermometers, including oral, rectal, ear (tympanic) and forehead (temporal artery) thermometers.
- Although it’s not the most accurate way to take a temperature, you can use an oral thermometer for an armpit (axillary) reading:
- Place the thermometer in the armpit and cross your arms or your child’s arms over the chest.
- Wait four to five minutes. The axillary temperature is slightly lower than an oral temperature.
If you call your doctor, report the actual number on the thermometer and where on the body you took the temperature.
Use a rectal thermometer for infants:
- Place a dab of petroleum jelly on the bulb.
- Lay your baby on his or her tummy.
- Carefully insert the bulb 1/2 to 1 inch (1.3 to 2.5 centimeters) into your baby’s rectum.
- Hold the bulb and your baby still for three minutes.
- Don’t let go of the thermometer while it’s inside your baby. If your baby squirms, the thermometer could go deeper and cause an injury.
