加减正气散类方5首出自《温病条辨》，源于藿香正气散，着眼于调整气机、平衡中焦，用于治疗三焦湿郁、秽湿着里所致的脾胃病证。其中一加减正气散应用苦辛微寒法，主治湿郁气滞所致脾胃不适；二加减正气散应用苦辛淡法，主治湿阻经络之证，注重清表里、经络之湿；三加减正气散应用苦辛寒法，针对湿重于热的中焦湿热证；四加减正气散和五加减正气散应用苦辛温法，主治中焦寒湿证。其组方突出“衡”之特色，注重气机升降、用药寒温及治法通补、温清平衡，临床可拓展应用至暑湿外感、温疫等外感病及兼有中焦湿热的内伤杂病。

Five categorized formulas of Jiajian Zhengqi Powder(加减正气散) are derived from Systematic Differentiation of Warm Diseases,and originated from Huoxiang Zhengqi Powder(藿香正气散). Focusing on regulating qi movement and balancing the middle energizer,they are indicated for treating spleen-stomach disorders caused by damp stagnation in the triple energizer and internal retention of turbid dampness. Among them,the First Jiajian Zhengqi Powder uses the acrid-bitter and slightly cold method,and is mainly indicated for spleen-stomach discomfort due to dampness and qi stagnation. The Second Jiajian Zhengqi Powder adopts the acrid-bitter and bland method,targeting syndrome of dampness obstructing meridians and emphasizing on clearing dampness from the exterior,interior and meridians. The Third Jiajian Zhengqi Powder applies the acrid-bitter and cold method,for treating damp-heat syndrome of the middle energizer with dampness prevailing over heat. The Fourth and Fifth Jiajian Zhengqi Powders use the acrid-bitter and warm method,and are mainly indicated for damp-cold syndrome of the middle energizer. The composition of these formulas highlights the characteristic of “balance”,focusing on the balance of ascending and descending of qi movement,cold and warm properties of medicinal herbs,dredging and tonifying,as well as warming and clearing in therapeutic methods. Clinically,their application can be extended to exogenous diseases such as exogenous summer-dampness and pestilence,and internal miscellaneous diseases complicated with damp-heat syndrome of the middle energizer.