Agarwood (Aquilaria Sinensis), Qingmuxiang (Aucklandiae Radix), Wuxijiao (Rhinocerotis Cornu), Xiangfuzi (Cyperi Rhizoma), Dingxiang (Caryophylli Flos), Zhusha (Cinnabaris), Helile (Terminalia Chebulae Fructus), Baitanxiang (Santalum Album Lignum), Shexiang (Moschus), Bibo (Piperis Longi Fructus), Naozhang (Borneolum Syntheticum), Baizhu (Atractylodis Macrocephalae Rhizoma), AnxiXiang (Resina Benzoin), Suheyou (Styrax Liquidus) (each 2 liang), Xunluxiang (Olibanum / Boswelliae Resina) (1 liang).

The patient suffers from **Zhongfeng** (Stroke/Cerebral Apoplexy), with phlegm obstructing the throat, making it difficult to swallow water or food. Only aromatic and penetrating substances can open the orifices; therefore, a collection of various aromatic herbs is gathered to facilitate the opening of the orifices. Only pungent and hot substances can unblock obstructions; therefore, various pungent herbs are used as assistants and guides. Although **Xijiao** (Rhinoceros Horn) is cool, its cooling nature does not cause stagnation; although **Helile** (Chebulic Myrobalan) is astringent, its astringency generates body fluids. When people in the country use this formula for stroke, it often yields effective results. Zhu Danxi argued that pungent and aromatic drugs dissipate true Qi, and further claimed that Naozhang (Camphor) and Shexiang (Musk) can draw wind pathogens into the bones, like oil penetrating flour, which is incomprehensible. Physicians should only use this formula for emergency rescue and must strictly warn against frequent consumption.

Xu Yinzong was from Yixing, Changzhou, during the Tang Dynasty. He initially served in the Chen Dynasty as the External Military Adjutant to Prince Xincai. At that time, Empress Dowager Liu suffered from stroke and could not speak; her pulse was deep and tight. Xu Yinzong said, "Since oral medication cannot be taken, decoction steam should be used for fumigation, allowing the medicinal properties to enter the **Couli** (interstices of skin and muscle). Recovery can be expected within one double-hour period." Consequently, he prepared dozens of hu (ancient unit of volume) of Huangqi Fangfeng Tang (Astragalus and Saposhnikovia Decoction), placed them under the bed, and the vapor spread like smoke. The next day, the Empress Dowager regained her speech. For this, he was promoted to Governor of Yixing. I hold that nasal qi connects with Heaven; thus, formless Qi enters through the nose, transmits and transforms via respiration, reaching everywhere. Huangqi (Astragali Radix) is sweet and good at tonifying; combined with Fangfeng (Saposhnikoviae Radix), its efficacy becomes even faster, achieving both the expulsion of wind and the tonification of deficiency. Without Xu Yinzong's profound understanding, he could not have presided over this method. If physicians can skillfully apply this method, it can also be used to treat contemporary patients.

Banxia (prepared with ginger juice), Chenpi (peel removed), BaiFuling (peel removed, equal parts of each), Gancao (honey-fried, half the dose).

When excessive wind leads to phlegm obstruction, after using medicines such as Xixian San (Thin Saliva Powder) to open the airway, this formula is subsequently used as the main treatment.

Wind damaging the Spleen leads to phlegm congestion; however, the generation of phlegm originates from Dampness. Banxia dries Dampness, and Fuling leaches out Dampness; once Dampness is removed, there is no source for phlegm generation. The harm caused by phlegm originates from Spleen deficiency and Qi stagnation. Gancao tonifies the Spleen, and Chenpi promotes Qi circulation; by tonifying the Spleen and promoting Qi, the Earth element is sufficient to control Dampness, and phlegm congestion will cease. This is the principle of Erchen Tang. It is named "Erchen" (Two Aged Ingredients) because Chenpi (Tangerine Peel) and Banxia (Pinellia Tuber) are prized for being aged. Detailed examination can be found in the Phlegm Disease section.