Is taking body temperature while asleep accurate?
May 11, 2023
Source: Cainiu Health
Dr. Yang Shuwen
Introduction
In general, if body temperature is measured right after falling asleep, the result is mostly accurate. However, if measuring after having been asleep for a long time, the reading is usually inaccurate. It is recommended to rest adequately for half an hour before taking the measurement, and to avoid vigorous physical activity. When measuring, it's best to use a mercury thermometer, ensuring the mercury column is below 35°C, and to dry the armpit thoroughly.
Under normal circumstances, if body temperature is measured right after falling asleep, the result is mostly accurate. However, if a person has been asleep for a long time, the temperature reading taken at that point is generally inaccurate. The detailed analysis is as follows:
1. Accurate
Right after falling asleep, the body temperature does not change immediately and the body remains in a relatively stable state. Therefore, a temperature measurement taken at this time is relatively accurate. If the measured temperature appears elevated, it is advisable to use warm water sponging to help reduce it. When necessary, antipyretic medications such as acetaminophen, ibuprofen, or indomethacin may be used under medical guidance.
2. Inaccurate
Body temperature naturally fluctuates in a circadian rhythm, being lowest between 2:00 and 6:00 AM and highest between 1:00 and 6:00 PM. After being asleep for some time, metabolic activity and energy consumption decrease, leading to reduced heat production and a gradual drop in body temperature. Measuring temperature during this period often yields inaccurate results, potentially showing lower-than-normal readings.
It is recommended to rest adequately for at least half an hour before taking a temperature measurement, avoiding vigorous physical activity. A mercury thermometer is preferred; ensure the mercury column is below 35°C before use, and dry the armpit thoroughly prior to measurement.
