Erchen decoction is the fundamental prescription for treating phlegm-damp syndrome and has been praised as "the general prescription for resolving phlegm" by physicians in the past dynasties. Children are constitutionally frail and prone to dampness retention and phlegm production due to dysfunction of the spleen in transportation; internal obstruction by phlegm-dampness can lead to multiple system disorders involving the respiratory, digestive and emotional systems. Considering the physiological characteristics of children such as "inherent splenic insufficiency" and "inherent pulmonary insufficiency", and based on the pathogenic theory that "the spleen is the source of phlegm production and the lung is the container for phlegm storage", Professor Dong Youqi adheres to the therapeutic principle of "regulating qi first for phlegm treatment and invigorating the spleen to cut off the source of phlegm". He flexibly applies Erchen decoction and its derivative prescriptions including Wendan decoction and Liujunzi decoction, with modifications tailored to syndromes, addressing both the symptoms and the root causes of the disease. These prescriptions have been widely used in the treatment of phlegm-dampness-related pediatric disorders such as cough, food stagnation, anorexia, vertigo, insomnia and emotional disorders, achieving remarkable therapeutic effects. This paper cites three typical medical cases as evidence, reflecting Professor Dong's academic thought of "diagnosing diseases and formulating treatments based on theoretical inference", and providing valuable clinical experience for the application of Erchen decoction and its derivative prescriptions in the treatment of infantile phlegm-damp syndrome.
