TCM's Vivid Description of Fever: Exterior and Interior

Fever, also called pyrexia, arises when prior causes such as cold and wind allow viruses and bacteria to invade the human body, setting up a struggle between vital qi and pathogenic qi; when body temperature rises more than 0.5°C above normal, it is fever. A person's normal body temperature also varies with individual differences, and is further affected by the seasons of spring, summer, autumn and winter and by the specific climate and environment of certain periods; in women, factors such as menstruation and other gynecological conditions and childbirth also affect body temperature.

Measuring Body Temperature

For this reason, every person should regularly measure, keep records of and analyze their own body temperature, but most people do not yet have this awareness, so they often judge whether there is fever by the different sites at which temperature is taken; for example, if the axillary temperature exceeds 37.4°C, it is fever, and in terms of time, the measurement is taken for 10 minutes. As for the causes of fever, besides the disease-causing viruses and bacteria described above, there are other causes, such as collagen diseases, that is, connective tissue diseases, and malignant tumors.

In TCM, human fever is differentiated separately from the two aspects of external contraction and internal damage. In external contraction, it is described as being affected by the six excesses and external pathogens, or by pestilential qi, rather than speaking of viruses and bacteria, and the onset is mostly an excess pattern, called in ancient times cold damage, epidemic disease and warm disease. Internal damage fever is explained in TCM as being caused by diet and overexertion or by changes in the seven emotions, which lead to an imbalance of yin and yang in the human body and deficiency and decline of qi and blood, so it is mostly a deficiency pattern. Examples include yin deficiency with dry heat, yang deficiency fever, blood deficiency fever, qi deficiency fever, consumptive fever, yang floating fever, fever from blood loss, and five-center heat.

Looking at Body Temperature

The outstanding Chinese medical tradition describes human fever in an all-encompassing and thorough way. For example, in terms of fever types, it further distinguishes slight heat, strong heat, aversion to heat, tidal fever, violent heat, fever with aversion to cold, alternating cold and heat, and five-center heat, and there are also differences in fever according to time and body part. In terms of time, for example, there is dusk fever, fever at dawn, daytime heat and nighttime heat. In terms of body part, there is muscle heat, heat of the ulnar skin, heat over the shoulders, heat of the elbows, heat of the palms, heat of the feet, heat of the four limbs, heat of the back and heat of the backs of the hands, and so on. Moreover, in terms of pattern differentiation, there are also food accumulation fever, blood stasis fever, static accumulation fever, fever from drinking alcohol, and residual heat after illness.