Early autumn is when the weather turns demonstrably cool and the air becomes dry. We often hear people around us coughing uncontrollably, especially in crowded public places or on public transport. It is possible that they are suffering from upper respiratory tract diseases.

Coughing is an upper respiratory tract ailment. The upper respiratory tract includes the nose, nasal passages, nasal cavity, throat and windpipe. Upper respiratory tract infections such as acute and chronic bronchitis, bronchiectasis, pneumonia and chronic laryngitis are usually accompanied by coughing.

In TCM, coughing is mainly divided into external infection coughing and internal injury coughing. The former is due to the invasion of the lungs and the upper respiratory tract by the Six Excessive Atmospheric Influences (wind, cold, heat, moisture, dry heat and fire). The latter occurs due to the dysfunction of internal organs spreading to the lungs. Coughing is very closely related to qi and phlegm; it is categorised into three categories: audible coughing without phlegm (ke), inaudible coughing with phlegm (sou) and audible coughing with phlegm (kesou).

External infection coughing is usually caused by to the invasion of the lungs and the upper respiratory tract by the Six Excessive Atmospheric Influences. However, all four seasons are different and the invading influences are also different. Hence, the symptoms of coughing are expressed differently: winter-cold, spring-heat, summer-moist and autumn-dry heat. The most common infection within the four seasons is wind-cold coughing. The major atmospheric influence is caused due to the wind. External infection coughing is caused by the wind, and wind is the leading influence in the four seasons and the cold-influence, heat-influence, moist-influence and dry heat-influence brought about by Wind-Influence will cause wind-cold, wind-heat, wind-moist, wind-dry heat, etc.