Shen Zinan stated: The condition of "Zhong E" (Sudden Severe Poisoning), commonly known in folklore as "Jiao Chang Wu Sha" (Intestinal Twisting Black Miasma), is caused by foul and toxic miasmal qi entering directly from the mouth and nose into the heart and chest. This leads to obstruction and stagnation in the intestines, stomach, and zang-fu organs, hindering the movement of Zheng Qi (Upright Qi). Consequently, symptoms such as heart pain, abdominal distension, and constipation occur. This belongs to Excess patterns (Shi Zheng), seemingly not invaded by the Six Exogenous Pathogens (Liu Yin - Wind, Cold, Summerheat, Dampness, Dryness, Fire), nor does it present clear distinctions between Exterior/Interior, Deficiency/Excess, or Clear/Turbid. Therefore, Radix Crotonis Fructus (Badou, *Crotonis Fructus*)—a drug that is extremely hot, highly toxic, and drastic—is used to urgently attack and expel the pathogen. Semen Armeniacae Amarum (Xingren, *Armeniacae Semen Amarae*) is added to facilitate the Qi mechanism of the Lung and Large Intestine, allowing the pathogen to exit via stool, clearing everything away so that the disease may be cured. If delayed even for a moment, Zheng Qi will fail to circulate, and the mechanisms of Ying-Wei (Nutritive-Defensive) and Yin-Yang will cease, leading to death. This illustrates the principle that "patency relieves pain."

Question: When a person is ill, food intake naturally decreases. If this reduced intake is mistaken for Food Stagnation (Su Shi - undigested food retained in the stomach/intestines), doctors often mistakenly use digestive agents such as Fructus Crataegi (Shanzha, *Crataegi Fructus*), Shen Qu (Medicated Leaven), Rhizoma Atractylodis Macrocephalae combined with Pericarpium Citri Reticulatae (Zhiqi & Zhimu, though text implies Zhi Shi & Hou Po), which damage the Middle Qi (Spleen-Stomach Qi). This allows external pathogens to enter the interior through the deficiency, a phenomenon too numerous to count. However, if there truly is Food Stagnation, how can it be distinguished? The Master said: "The pulse of Food Stagnation should typically appear as Deep and Slippery at the Guan position. However, if the illness has persisted for a long time, this is not the case. When Grain Qi accumulates and becomes obstructed and abundant, the Cun Kou (Radial Artery at the wrist) pulse appears Floating and Large. Irregular diet injures the Yin; when Yin is injured, Blood is damaged first. Therefore, upon palpation, the pulse is not Slippery but instead Choppy (Se). Furthermore, due to obstruction of Middle Qi, the essence of water and grain cannot descend, causing the Chi position pulse to also be Faint and Choppy. Thus, within the Faint and Choppy qualities, one knows that the injury is due to Food Stagnation, and Da Cheng Qi Tang (Great Order the Yang Decoction) should be administered."

A pulse that is Rapid and Slippery indicates an Excess state and abundant Grain Qi, confirming the presence of Food Stagnation. (One might wonder: why was the Faint-Choppy pulse associated with Food Stagnation earlier, while now the Rapid-Slippery pulse is also associated with it? One must understand that when Food Stagnation causes injury, the pulse manifests as Faint-Choppy; however, the intrinsic pulse of Food Stagnation itself is Rapid-Slippery. Although the new and old presentations differ, the source of the disease is identical.) Treatment with purgation will lead to recovery. (Da Cheng Qi Tang is appropriate.) In cases of chronic diarrhea where there is no desire to eat, it is due to Spleen injury preventing digestion. However, if there is no desire to eat at the onset of diarrhea, this indicates Food Stagnation ("Injury from food leads to aversion to food"). It should be treated with purgation, using Da Cheng Qi Tang.

These three sections discuss syndromes of Food Stagnation suitable for purgative therapy.

Referencing various scholars' opinions: The Spleen and Stomach are responsible for transforming water and grain and circulating Jin-Ye (Body Fluids) and Qi; they cannot function without continuity. If grain stagnates, transformation ceases; if Qi stagnates, vital mechanisms halt. If transformation ceases and mechanisms halt, human life ends abruptly. Therefore, Da Cheng Qi Tang must be used to rapidly eliminate stagnant grain. Once the grain is removed, Qi moves; once Qi moves, transformation continues, preserving life. If one merely uses Ping Wei San (Calm the Stomach Powder) or digestive aids like Germinatus Hordei (Maiya, *Hordei Fructus Germinatus*), Germinatus Oryzae Sativae (Guyaya, *Oryzae Germens*), Fructus Crataegi (Shanzha), and Shen Qu, the Food Stagnation has no outlet, while the Sheng Qi (Vital Qi) is consumed day by day. This is not only ineffective but harmful. Physicians must know how to return to the correct path.

Da Cheng Qi Tang Formula (See Chapter on Spasm Diseases)

(If Food Stagnation is in the Upper Wan (Upper Stomach), there is pain in the diaphragm region accompanied by vomiting; this is suitable for emesis but not purgation. If in the Middle Wan (Middle Stomach), there is epigastric pain with or without vomiting; both emesis and purgation may be used. If in the Lower Wan (Lower Stomach), there is periumbilical pain without vomiting; this is unsuitable for emesis but suitable for purgation. Now,) if Food Stagnation is in the Upper Wan, emesis should be induced using Gua Di San (Melon Sepal Powder).

This section discusses syndromes of Food Stagnation suitable for emetic therapy.

Gua Di San Formula

Gua Di (Melon Sepal, *Momordicae Fructus*): 1 fen, roasted until yellow.
Chi Xiao Dou (Red Adzuki Bean, *Vigna angularis*): 3 fen, boiled.

Grind these two ingredients into a powder. Boil Xiang Chi (Fermented Soybean, *Sojae Semen Praeparatum*) 7 he in water to extract the juice. Mix one qian bi (approx. 2-3 grams) of the powder with the decoction and administer warm. If vomiting does not occur, slightly increase the dose. Stop when vigorous vomiting is achieved.

In summary, treatment relies on pulse diagnosis. The Floating-Large-Reversed-Choppy, Faint-Slippery, and Rapid-Slippery pulses mentioned above must be understood intuitively within their dynamic nature, as they cannot be fully conveyed by words. Determining Food Stagnation from a Tight pulse is particularly subtle and profound. A pulse that is Tight like a turning rope and variable/unpredictable indicates Food Stagnation.

Note: A Tight pulse is typically fixed for exterior contraction diseases. The difference lies in the term "variable/unpredictable" (Wu Chang), meaning it fluctuates between tight and not-tight.

A Tight pulse with headache resembles Wind-Cold, but actually indicates undigested Food Stagnation in the abdomen.

Note: A Tight pulse with headache resembling Wind-Cold means the pulse and symptom mimic Wind-Cold. However, Wind-Cold presents with aversion to wind/cold, stiff neck, and Floating pulse concurrently. Here, only headache is felt. Using the Tight pulse to diagnose Food Stagnation is the most subtle and difficult aspect of pulse diagnosis. You Zaijing's commentary captures the essence well.

You Zaijing stated: A pulse Tight like a turning rope and variable indicates that Tightness is combined with Slipperiness, unlike the Tightness of Wind-Cold exterior contraction, which is Tight and wiry (Xian). Cold constriction causes a Fixed Tightness; Food Qi generation causes alternating Tightness and Slipperiness, resembling fingers turning a rope, hence "variable." "Tight pulse, headache, resembling Wind-Cold" does not mean having both Food Stagnation and Wind-Cold simultaneously. It means that undigested Food Stagnation causes stagnant Qi to rise, resulting in headache that mimics Wind-Cold, but is essentially Food Accumulation resembling Taiyang disease (Shang Han). Zhang Zhongjing feared people would mistake this for an exterior pathogen and induce sweating, so he presented this example, stating: "There is undigested Food Stagnation in the abdomen," implying a profound intent.