Emotional Stress
Worry is a frequent emotional cause of cough. It affects the Lungs directly and it knots Qi
preventing the descending of Lung-Qi. This type of cough would be dry and irritating.
Prolonged anger, frustration, or resentment lead to stagnation of Liver-Qi and, over a long period
of time, to Liver-Fire. This may invade the Lungs and prevent the descending of Lung-Qi,
causing cough.
Diet
Excessive consumption of sweets, greasy foods and dairy foods may lead to the formation of
Phlegm which settles in the Lungs and prevents Lung-Qi from descending. This causes a cough
with profuse expectoration.
Excessive consumption of hot foods, alcohol and fried-greasy foods leads to the formation of
Heat and Phlegm. Phlegm settles in the Lungs and impairs the descending of Lung-Qi, while
Heat dries up the Lung fluids. Both these processes cause cough.
Chronic Illness
A chronic illness affecting the Lungs weakens Lung-Qi and/or Lung-Yin. The deficient Lung-Qi
fails to descend and causes a chronic cough of the Empty type.
Thus the pathology of cough is always characterized by Lung-Qi failing to descend. This may
happen either because the Lungs are obstructed by an exterior or interior pathogenic factor
(Full-type) or because Lung-Qi is deficient and fails to descend properly (Empty-type).
Pathogenic factors in the Lungs which impair the descending of Qi include external Wind, Heat,
Phlegm, stagnation of Qi and Liver-Fire. In such cases when Qi fails to descend because of a
pathogenic factor, it is said to be "rebelling upwards". All the old classics convey this idea of
cough being caused by rebellious Qi. The "Simple Questions" in chapter 10 says: "Cough
consists in Qi rebelling upwards."8(157) The "Prescriptions of the Golden Chest" by Zhang
Zhong Ying says: "Cough is due to Qi rebelling upwards."9(158) External coughs are therefore
by definition of the Full type.
Interior coughs may be of the Deficiency or Excess type and the main pathology in the Excess
type is Phlegm or Fire. Phlegm combines with Heat or Cold and Fire may be of the Excess or
Deficiency type.
Thus coughs may be classified in various ways. Using Fullness and Emptiness, we may classify
them as follows: