Erchen Literature Studies

Erchen Tang (Decoction of Pinellia and Perocarpirum) comes from Taiping Huimin Hejiju Fang (Benevolent Prescriptions from Taiping Pharmaceutical Bureau) of Song Dynasty and is regarded as the representative decoction for removing the phlegm in the science of Chinese prescriptions. This article focuses on literature analysis of it from the following six aspects: the origin of Erchen Tang (Decoction of Pinellia and Perocarpirum), significance of the composition, the principle of applying Erchen (Erchen Tang (Decoction of Pinellia and Perocarpirum)) for all phlegm syndromes, comparison of Erchen Tang {Decoction of Pinellia and Perocarpirum) and other similar prescriptions, experience of some famous historical doctors employing Erchen Tang (Decoction of Pinellia and Perocarpirum), special effect of Wumei (Fructus Mume) in Erchen Tang (Decoction of Pinellia and Perocarpirum) , whether Banxia (Rhizoma Pinelliae) Chenpi (Pericarpium Citri Reticulatae) the old the better.The results suggest that the action of Erchen Tang (Decoction of Pinellia and Perocarpirum) for removing phlegm and regulating the stomach qi came from Neijing (Canon of Internal Medicine). While the action for removing phlegm and dampness stagnation came from Jingui Yaolue (Synopsis of Prescriptions of the Golden Cabinet). The knowledge of phlegm diseases were obtained earlier before Sui and Tang Dynasty. One is that the combination of Banxia (Rhizoma Pinelliae) and Chenpi (Pericarpium Citri Reticulatae) is good for removing phlegm. The other is that the main treating method for removing phlegm is to regulating qi activities. It was said that "the first therapy for removing phlegm is to regulate qi activities. The phlegm will be removed after qi flows smoothly." That was the origin of Erchen Tang (Decoction of Pinellia and Perocarpirum). In addition, we found out that the phase Erchen inthe principle of applying Erchen (Erchen Tang {Decoction ofPinellia and Perocarpirum)) for all phlegm syndromes refers to Erchen Tang {Decoction ofPinellia and Perocarpirum) and similar decoctions as well as the principle of removing phlegm by employing Erchen Tang {Decoction of Pinellia and Perocarpirum). The similar decoctions of Erchen Tang {Decoction of Pinellia and Perocarpirum) were formed by modification of the original decoction; therefore, the actions and indications developed a lot. That is to say the actions of the original decoction are to remove the dampness and phlegm and regulate the qi activities in the middle energizer. While the actions of modified decoctions changed to relieve the extc. 'or syndrome, clear away heat, remove pathogenic cold, regulate qi activities, improve digestion, reinforce health qi, remove dampness and phlegm. The indications changed in accordance with the change of actions. Famous doctors in the history such as Zhu Danxi, Li Yongcui, Zhang Lu, and Cheng Zhongling etc. had cried up the decoction and improved its action though clinical experience. The special effect of Wumei {Fructus Mume) in Erchen Tang {Decoction of Pinellia and Perocarpirum) should be paid more attention to. Banxia {Rhizoma Pinelliae) and Chenpi {Pericarpium Citri Reticulatae) go with the principle "the old the better", however, the best effect doesn't necessarily come after the oldest drugs.This article serves as reference of Erchen (Erchen Tang {Decoction of Pinellia and Perocarpirum)) and similar decoctions for the clinical application, teaching, and acpderrvc activities as well as Pathology of Phlegm Science in TCM.