Library

After purgation for warm epidemic, the pulse and symptoms have both normalized. However, there are masses in the abdomen that cause pain upon pressure; the patient feels obstruction and abdominal distension/fullness. Occasionally, there is qi moving up and down without smooth flow, often producing sounds resembling frog croaking. This indicates that the pathogenic factor has been exhausted, but the accumulated residue remains. In this case, aggressive purgation must not be used. Purgation would merely deplete Yuan Qi (Original Qi); with Qi deficiency, peristalsis becomes even more difficult, ultimately failing to resolve the accumulation. Diet should be gradually resumed until Stomach Qi recovers slightly, fluids circulate, and stool naturally moistens and passes. I once encountered a case where, after recovery, the patient consumed congee for half a month before the mass was passed; it was hard, black, and stone-like.

Following recovery from warm epidemic, the pulse and symptoms are normal, but defecation does not occur for twenty to thirty days. There is frequent vomiting and inability to eat or drink. Even small amounts of liquid induce worse vomiting. This is termed "Lower Obstruction" (Xia Ge). Since the lower pathway is blocked, Qi inevitably rebels upward. If mistakenly diagnosed as "Reversal Vomiting" (Fan Wei) and treated with Niuhuang (Calculus Bovis) or Goubao (Dog Gallstone), or if mistaken for Cold Qi and treated with Huoxiang (Agastache Herba), Dingxiang (Caryophylli Flos), or Erchen Tang (Two-Aged Decoction), these are errors. The appropriate treatment is Hot Administration of Tiaowei Chengqi Tang (Stomach-Regulating Purging Decoction) taken in one dose. This will promptly expel old accumulations, loose stools, and sticky foul-smelling waste, immediately stopping the vomiting. This illustrates the principle: "To seek the south wind, one must open the north window." After vomiting stops, do not hastily tonify. Administering Renshen (Ginseng Radix et Rhizoma) even in small amounts may cause re-obstruction of the Lower Jiao (Lower Burner) and recurrence of vomiting. This resembles the previous condition of residual accumulation post-recovery, but differs in that the presence of "frog-like sounds" allows the patient to eat without vomiting. Thus, a slight difference leads to vastly different outcomes. In both cases, defecation is blocked, the pulse is calm, and the body is cool; the difference between safety and danger lies solely in whether Qi is unobstructed or obstructed.

There are approximately thirty-plus indications for purgation in warm epidemics; all need not be present. If yellow tongue coating and epigastric/abdominal fullness/stuffiness are observed, Dahuang (Rhei Radix et Rhizoma) can be added to Dayuan Yin (Origin-Reaching Decoction) to purge. If the pathogen is at the Membrane Source (Mo Yuan - a location between exterior and interior) and shows signs of movement, on the verge of leaving but not yet gone, Dahuang promotes its downward expulsion. This is indeed a method of "opening the door to drive out the thief." Even if not fully cured, the pathogen cannot linger. Two or three days later, if residual pathogens enter the Stomach, Xiao Chengqi Tang (Minor Purging Decoction) should still be used to clear remaining toxins. Generally, external pathogens require early treatment while Qi and Blood are undisturbed, muscles are not wasted, and fluids are not depleted, preventing critical danger and facilitating easier recovery. The strategy for perfection is simply knowing the location of the pathogen and removing the root cause early. One must assess the patient's Deficiency/Excess, weigh the severity of the pathogen, observe the speed of the disease, and estimate how much the pathogen has moved from the Membrane Source. Only then can medicine be administered accurately, avoiding excess or insufficiency. Therefore, Zhang Zhongjing established the Three Chengqi Decoctions starting from Da Chaihu Tang (Major Bupleurum Decoction), varying dosages according to severity. Do not adhere rigidly to the saying that "purgation should not be delayed." For indications requiring purgation, if no dry feces are seen, one might wrongly consider purgation premature; or for non-indications, purgatives might be wrongly given. It is unknown that Chengqi Decoctions are designed to expel pathogens, not specifically for dry feces. Waiting until feces become hard and blood is bound by heat, leading to successive complications, is like nurturing a tiger and leaving trouble behind—a doctor's fault. Moreover, many cases involve loose stools that, due to failure to purge early, are steamed into extremely foul-smelling substances like spoiled sauce or lotus root mud, never hardening even until death. Once this filth is removed, the toxic pathogen dissipates, and pulse/symptoms recede. Why insist on waiting for hard feces? For individuals with dry blood and empty meridians, or the elderly with deficient blood, dry constipation often occurs; similarly, post-illness Qi/Blood deficiency often leads to dryness. As stated in classics, ten days without bowel movement without discomfort causes no harm. Thus, dryness itself does not harm; the toxic pathogen is fatal. Know that pathogenic heat causes dryness, not vice versa. However, in prolonged illness with failed purgation, dryness blocks Qi, trapping stagnant pathogens and heat, making release difficult. Once hard feces pass, Qi flows, and pathogenic heat is released—this is the difference between early and late stages. Ultimately, the pathogen is the root, heat is the branch, and dry feces are the branch of the branch. If the pathogen is removed early, why worry about dryness?

In the case of Dysentery (Zhixia), there is typically no dry feces. If the constitution is solid initially, with frequent, urgent, and difficult defecation, Shaoyao Tang (Peony Decoction) with added Dahuang should be used for purgation. Is this also due to dry feces? Regarding Accumulation (Ji), if only existing accumulation is treated, new accumulation will form. Dahuang must be used to expel the pathogen, cutting off the source of accumulation. With free Ying and Wei (Nutritive and Defensive Qi), accumulation heals spontaneously. Note that Deficient Dysentery falls outside this discussion.

Question: If pulse and symptoms are identical, why is feces sometimes hard and sometimes soft? Answer: In some cases, upon severe illness, bowel movement ceases immediately, followed by internal heat generation, which steams the contents into hardness. In others, who normally have loose stools, even with intense Stomach/Intestine heat, the stool becomes extremely foul and sticky but never hardens until death. Applying the classic rule "initially hard then loose means do not purge" to cases requiring purgation is a千古 (eternal) error.

Da Chengqi Tang (Major Purging Decoction):
Dahuang (Rhei Radix et Rhizoma) (5 qian), Houpo (Magnoliae Officinalis Cortex) (1 qian), Zhishi (Aurantii Fructus Immaturus) (1 qian), Mangxiao (Natrii Sulfas) (3 qian).
Decoct in water with Shengjiang (Zingiberis Rhizoma Recens). Reduce dosage by half for weak patients; halve again for mild pathogens.

Xiao Chengqi Tang (Minor Purging Decoction):
Dahuang (Rhei Radix et Rhizoma) (5 qian), Houpo (Magnoliae Officinalis Cortex) (1 qian), Zhishi (Aurantii Fructus Immaturus) (1 qian).
Decoct in water with Shengjiang (Zingiberis Rhizoma Recens).

Tiaowei Chengqi Tang (Stomach-Regulating Purging Decoction):
Dahuang (Rhei Radix et Rhizoma) (5 qian), Mangxiao (Natrii Sulfas) (2.5 qian), Gancao (Glycyrrhizae Radix et Rhizoma) (1 qian).
Decoct in water with Shengjiang (Zingiberis Rhizoma Recens).

Note: The functions of the three Chengqi Decoctions are similar. For Heat entering the interior causing only upper Jiao fullness, use Xiao Chengqi Tang. For firm accumulation in the middle, add Mangxiao to soften hardness. For old accumulation with stasis-heat, Tiaowei Chengqi Tang is suitable. The efficacy of all three relies primarily on Dahuang; others treat branches. For those unable to tolerate decoctions due to vomiting or aversion, grind into powder, form honey pills, and take with water.