Mr. Lu Jiuzhi stated: Among the four conditions—danzha (scarlet fever-like rash), shazhen (shagreen and maculopapular rash), ban (maculae), and zhen (papules)—dan and shazhen are of the same category, while ban and zhen are of the same category. Shazhen is mild whereas dan is severe; zhen is mild whereas ban is severe. Dan and ban emerge flat upon the skin surface forming patches, whereas shazhen and zhen protrude above the skin surface forming dots. Shazhen is shazhen, dan is dan; generally speaking, they may be collectively referred to as shazhen. Zhen is zhen, ban is ban; generally speaking, they may be collectively referred to as zhen.

However, the origin of shazhen lies in the Lung (Zang organ). Because pathogenic shazhen factors are present first, exterior heat symptoms appear. To treat shazhen, one should target the Lung, primarily employing methods of ascending and venting (releasing pathogens from the exterior), with a slight addition of cooling agents. The origin of zhen lies in the Stomach (Zang organ). Because exterior heat has not resolved and has transformed into interior heat, accumulating to form pathogenic zhen factors, to treat zhen, one should target the Stomach, primarily employing cooling methods, with a minor addition of ascending and venting agents.

When the primary treatment should be exterior dispersing, cold purgatives must not be used too early for shazhen. When the primary treatment should be bitter cold draining,辛散 (acrid dispersing) methods must not be employed again for zhen. Generally speaking, ascending and venting mainly refers to herbs such as Shengma (Cimicifugae Rhizoma), Gegen (Puerariae Lobatae Radix), and Chaihu (Bupleuri Radix); cooling mainly refers to herbs such as Huangqin (Scutellariae Radix), Zhizi (Gardeniae Fructus), Sangye (Mori Folium), and Mudanpi (Moutan Cortex). As long as one follows the principle of Gegen Qinlian Tang (Kudzu and Scutellaria Decoction) established by Zhang Zhongjing, making appropriate modifications, one can accurately address the subtle nuances of the condition at this stage without error. This is the essential approach to treating shazhen.

Historically, those treating these conditions have either advocated acrid dispersing and prohibited cold purging, or advocated cold purging and prohibited acrid dispersing, thus failing in both aspects. Regarding dan and ban, however, they represent extreme interior heat. Only large doses of cold medicines can effectively handle them; they cannot be compared merely to shazhen and zhen.

For any of these four conditions, there will inevitably be chest and epigastric stuffiness. Whether these four conditions are resolving or not is distinguished by whether the chest and epigastric stuffiness has resolved or not. For any of these four conditions, the fever will necessarily be vigorous. Whether these four conditions are resolving or not is distinguished by whether sweating is thorough or not.

Therefore, when conducting standard treatment for shazhen, one must simultaneously employ both ascending/clearing and cooling methods, treating both the exterior and interior, ensuring that the shazhen and sweat emerge together. However, when shazhen is at the stage of eruption, patients often suffer from unbearable chest stuffiness. If they move even slightly, the spots may retract, and the pathogenic factors may sink inward. This does not necessarily imply an external wind pathogen; even slight negligence regarding sleeves or blankets can cause sweat to recede. Once sweat recedes, the entire body quickly becomes dry.

At this point, two fatal dangers arise: first, when sweat just begins to emerge, pores open completely, allowing new wind pathogens to easily enter; second, after profuse sweating, further sweating is contraindicated. Not only will the shazhen immediately retract, but since fluids have been depleted, heat will become even more intense. All subsequent complications arise from this. Patients believe the illness is unresolved, and physicians attribute it to disease transformation, unaware that it is due to improper sweating management.

This applies to all diseases suitable for resolution through sweating, but is particularly critical in cases complicated by shazhen. Therefore, this issue is specifically highlighted here.