Library

Both the Baihu Tang (White Tiger Decoction) and Baihu Jia Renshen Tang (White Tiger plus Ginseng Decoction) are used to treat excess heat in the Foot-Yangming channel. When heat enters the Fu-organ of the Hand-Yangming (Large Intestine), causing dryness and constipation of the stool due to heat, the more severe the dryness and constipation, the deeper the accumulated heat. In such cases, unless the dryness and constipation are opened up, the heat certainly cannot be eliminated. Therefore, purgative agents, such as the Chengqi Tang formulas, are essential.

Original text from *Shanghan Lun* (Treatise on Cold Damage): "In Yangming disease, if the pulse is slow, although there is sweating and no aversion to cold, the body will feel heavy, there will be shortness of breath, abdominal fullness, and wheezing. If there is tidal fever, it indicates that the exterior syndrome has resolved, and interior attack is permissible. If there is continuous sweating on the hands and feet, this indicates that the stool has become hard; Dachengqi Tang (Major Order the Qi Decoction) should be administered. If there is profuse sweating with slight fever and aversion to cold, the exterior pathogen has not yet resolved, and the heat is not tidal; Chengqi Tang should not be given. If there is significant abdominal fullness and obstruction, Xiaochengqi Tang (Minor Order the Qi Decoction) may be given to mildly harmonize the Stomach Qi, avoiding drastic purgation."

The first sentence mentions "Yangming disease with a slow pulse," which is the first clear sign indicating that Yangming disease with a slow pulse warrants purgation. Initially, I interpreted this sentence to mean that for all Shanghan (Cold Damage) Yangming cases requiring purgation, if the pulse is rapid, purgation often fails to resolve the condition. Thus, mentioning a slow pulse here does not necessarily mean slower than a normal pulse, but rather indicates the absence of rapidity, ensuring one need not worry about the failure of purgation afterward. However, after extensive clinical experience, I realized that Yangming diseases requiring purgation can indeed present with a slow pulse. Yet, this slowness is not merely sluggish; it resembles a state where accumulation reaches its peak before breaking through, presenting a pulse that is slow yet prominent. This slowness is caused by obstruction in the intestines. The fact that the slow pulse becomes prominent is because Yangming fire is flourishing, and the pulse is originally forceful; something obstructs the force of the pulse, making it slow, which precisely激ates (stimulates/excites) the pulse's force, creating a jumping sensation. Explaining the slow pulse in this way makes the rationale for purging based on a slow pulse self-evident.

However, since my clinical practice, I have known that when Yangming disease requires purgation, a slow pulse definitely permits purgation, and even if the pulse is neither slow nor rapid, purgation is also permissible. Only when the pulse is rapid or beats six times per respiration (extremely rapid) should purgation be avoided. Forcing purgation in such cases will certainly fail to resolve the disease or exacerbate it. For such syndromes, I originally devised an alternative purgative method: using Baihu Jia Renshen Tang, but not decocting the Shigao (Gypsum Fibrosum) into the soup. Instead, the fine powder of Shigao is taken with the warm decoction of the other herbs. Having used this formula successfully many times, I named it Baihu Chengqi Tang (White Tiger Order the Qi Decoction) and recorded it below for reference by the medical community.

Raw Gypsum Fibrosum (Shigao) 8 qian (crushed finely), Large Lu Dangshen (Codonopsis Radix) 3 qian, Tianmum (Anemarrhenae Rhizoma) 8 qian, Gancao (Licorice Root) 2 qian, Jingmi (Rice Grain) 2 qian. These five ingredients: decoct the last four in water to obtain 1.5 bowls of liquid. Take the fine powder of Raw Gypsum Fibrosum with warm herbal liquid in two doses. After the first dose, wait two hours. If there is no movement in the abdomen, take the second dose. If there is already movement in the abdomen, wait another half hour; if stool passes, stop further medication. If stool has not passed, take the second dose again. If the pulse is rapid but surging, slippery, and forceful, Dangshen may be omitted from this formula.

Previously, when encountering exogenous febrile diseases requiring purgation with a rapid pulse, I often prescribed large doses of Baihu Tang or Baihu Jia Renshen Tang, which could also facilitate bowel movement. However, Raw Gypsum Fibrosum had to be used in doses of 4-5 liang, decocted into a large bowl, and taken in divided warm doses for the stool to pass. Occasionally, after several doses, if the stool still did not pass, the patient would typically have a clean pulse and cool body temperature. Using a small amount of Xuanmingfen (Mirabilite) 2-3 qian mixed with honey and taken with boiled water could induce defecation. Nevertheless, this is not as convenient as using Baihu Chengqi Tang.

If Raw Gypsum Fibrosum is taken as a fine powder, its heat-clearing efficacy of 1 qian equals that of 0.5 liang when decocted. To promote bowel movement, 1 qian of powder equals 1 liang of decoction. Therefore, this formula uses only 8 qian of Raw Gypsum Fibrosum, administered cautiously in two divided doses.

In exogenous febrile diseases involving Yangming, when heat is extremely intense, prescribing large doses of Baihu Tang may reduce the heat slightly, but the next day the illness often returns to its original state. After repeating this several times, patients' families may suspect the medicine is incorrect and seek other doctors, leading to severe or fatal outcomes. Later, I formulated this prescription. Whenever Baihu Tang showed initial effect followed by recurrence, I would use Gypsum powder taken with the decoction during subsequent treatments. If the decoction contained 5-6 liang of Gypsum, the powder taken would be only 1 liang, at most 1.5 liang, and the heat would completely dissipate.

[Dachengqi Tang Formula] Dahuang (Rhubarb Root) 4 liang (washed with wine), Houpo (Magnolia Bark) 0.5 jin (roasted, skin removed), Zhishi (Immature Bitter Orange) 5 pieces (roasted), Mangxiao (Mirabilite) 3 he.

Take the above four ingredients, add 10 dou of water, first decoct the first two (Houpo and Zhishi), reduce to 5 sheng, remove dregs, add Dahuang, decoct to 2 sheng, remove dregs, add Mangxiao, boil gently for one or two boils, divide into two warm doses. If defecation occurs, do not take the remainder.

Dachengqi Tang is designed to unblock dryness and constipation in the intestines caused by heat. Therefore, Dahuang, which is good at purging and clearing heat, serves as the principal herb. However, the action of medicinal power relies on the qi transformation of the Zang-Fu organs to maneuver it. Thus, Houpo and Zhishi are added as assistants to circulate the stagnant qi transformation in the intestines, facilitating Dahuang's purgative action. Mangxiao is used for its cold nature and salty taste, which clears heat, softens hardness, and possesses purgative properties, making it easy to transform hard dry stool into loose stool for passage. The intent of this formula is thus: few ingredients, yet comprehensive and precise. However, I have doubts about this formula, specifically regarding the weight of the ingredients.

*Shennong Bencao Jing* states that Dahuang can push out the old and bring forth the new, hence its name "Huangliang" (Excellent Yellow). In Yangming conditions with excess heat and dry constipation, it is originally appropriate to use a larger dose. Houpo, however, is merely an assistant to Dahuang, yet it is heavily used at 0.5 jin, double the dose of Dahuang. Converting 1 liang to approximately 3 qian today, and dividing into two doses, each dose would contain about 1.2 liang (approx. 3.6 qian) of Houpo. Houpo is warm in nature and pungent in taste; excessive use damages true Qi, which is common knowledge. Its nature also allows it to spread outward to the surface, inducing hot sweating. I recall treating a case of Yangming excess heat with dry constipation in my youth. The formula used 3 qian of Dahuang, but the stool did not pass. Another doctor was consulted, who used 1 liang of Houpo. Shortly after taking it, the patient sweated profusely with hot sweat all over the body, appeared to pant but did not, had weak Qi insufficient for breathing, and died within half a day. This serves as a warning. Therefore, I believe the dosages in this formula must be erroneous. I suspect the dosage of Houpo should be half that of Dahuang, similar to Xiaochengqi Tang. The original text might have said "Houpo's dosage is half of Dahuang," which was mistakenly written as "half jin" (ban jin) instead of "half" (ban).

Furthermore, the section begins with "Yangming disease, slow pulse." Here, "slow pulse" means the pulse rate is not increased despite the presence of heat (not necessarily slower than a normal pulse). This indicates a patient who is physically robust with abundant Yin. If such a pulse appears when Dachengqi Tang is indicated, administering the original formula can be effective. However, such pulses are rarely seen in modern Dachengqi Tang cases. This difference is due to both timing and human factors, marking a distinction between ancient and modern times. Even if the original Houpo dosage was correct, physicians must adapt according to circumstances to truly follow Zhang Zhongjing. Otherwise, if the pulse is not slow but rapid, using only Xiao (Mirabilite) and Huang (Rhubarb) to purge might fail to resolve the disease due to Yin deficiency failing to overcome dryness-heat. How much more so would using heavy Houpo increase dryness-heat? Or if the pulse is not rapid but the heat is excess while the pulse is deficient, using only Xiao and Huang might lead to collapse after purging because the Qi is originally deficient and cannot withstand the pushing action of Xiao and Huang. How dare one use heavy Houpo and Zhishi to break the Qi? Ye Tianshi once added a parasol tree leaf to induce labor, which worked, but he mocked it. When asked why, he said, "I used one leaf on the day of Start of Autumn, symbolizing 'one leaf falls.' If it were not that time, what would be the purpose of using a parasol tree leaf?" Thus, famous doctors treat diseases by adapting to time and circumstances, never rigidly sticking to fixed rules. Therefore, when I use Chengqi Tang, I often use Dahuang and Mangxiao in doses of 7-8 qian, while Houpo and Zhishi are used only in 2 qian. Or, following the principle of Weitiao Chengqi Tang, I omit them entirely and add 5-6 qian of fine powder of Shizhe Shi (Ochre Hematite). This maintains the purgative power of Dachengqi Tang but is much safer. For rapid pulses, or pulses that feel hot but are weak upon deep pressure, I often first prescribe large doses of Baihu Jia Renshen Tang, decocted into a large bowl, taken in divided warm sips to clear dryness-heat in the Stomach. Moisture then moves from the Stomach to the Intestines, resolving dryness. Often, defecation occurs before the course is finished. Moreover, there is no fear of unresolved disease or collapse after purging. If defecation does not occur immediately, Xuanmingfen 3 qian or Magnesium Sulfate 4 qian can be mixed with honey and taken with boiled water. Alternatively, external treatment with pig bile enema, or salt water enema (salt derived from firing saltpeter is better) can induce defecation. After defecation, recovery is assured.

[Xiaochengqi Tang Formula] Dahuang 4 liang (wine-washed), Houpo 2 liang (roasted, skin removed), Zhishi 3 large pieces (roasted).

Take the above three ingredients, add 4 sheng of water, decoct to 1.2 sheng, remove dregs, divide into two warm doses. After the first dose, if bowel movement occurs, do not take the rest. If not, drink the entire amount.

Dachengqi Tang treats dry feces in the Large Intestine, hence Mangxiao is used to soften hardness. Xiaochengqi Tang treats significant abdominal fullness and obstruction, indicating the pathology lies in the Small Intestine extending to the Stomach. Therefore, only Dahuang and Houpo are used to open the Small Intestine. Once the Small Intestine opens and descends, defecation is not strictly necessary, and if it occurs, it will not be excessive. Food in the Stomach can descend to the Small Intestine, harmonizing Stomach Qi. This distinguishes the usage of Da and Xiao Chengqi Tangs. Additionally, Weitiao Chengqi Tang (Harmonize the Stomach Order the Qi Decoction) is discussed alongside these.

[Weitiao Chengqi Tang Formula] Dahuang 4 liang (skin removed, soaked in clear wine), Gancao 2 liang (roasted), Mangxiao 0.5 sheng.

Chop the ingredients, add 3 sheng of water, decoct to 1 sheng, remove dregs, add Mangxiao, boil gently until boiling, take in small warm doses.

Although Dahuang is a purgative, it is good at clearing heat from the Blood level. Irritability in the heart indicates Heat in the Blood. Soaking Dahuang in clear wine guides its bitter-cold nature upward to clear Heart Heat and relieve irritability. Mangxiao is used even without dry constipation because *Neijing* states: "For heat rampant inside, treat with salty-cold." Mangxiao is salty and cold, acting as the "opposite palace" of the Heart (Heart belongs to Fire, Salt belongs to Water). It excels at clearing Heart Heat. Gancao is used to slow the downward action of the drugs and harmonize the Stomach. Houpo and Zhishi are omitted because there is no dry constipation or abdominal fullness.

Although there are three Chengqi Tang formulas, Xiaochengqi and Weitiao Chengqi are variations of Dachengqi Tang. *Shanghan Lun* lists many indications for these three, but understanding their distinct intents and varying strengths allows one to treat upper, middle, and lower aspects appropriately. Treating the upper can affect the middle, and the middle can affect the lower; they are interconnected. Thus, one can judiciously choose the appropriate strength for Chengqi Tang indications without error. My use of Chengqi Tang is often flexible and not limited to these three formulas. I will cite several cases to demonstrate.

Dachengqi Tang is indicated for slow pulses, but can also be used for surging, solid, and forceful pulses. However, if the pulse is not slow but rapid, and one hastily prescribes Dachengqi Tang for dry constipation, patients with weak pulses risk collapse after defecation. Those with strong pulses may not collapse, but the disease will not resolve ("purge but not resolved"). For such pulses, one must first cure the rapidity before promoting defecation.

Case 1: An elderly man, nearly sixty, suffered from severe exogenous heat causing ten days of constipation. His pulse beat more than six times per respiration, with irritability and heat in the chest. Several doctors dared not use purgatives, having no other options. I found his pulse rapid but very solid upon deep pressure. I first prescribed large doses of Baihu Jia Renshen Tang, taken in three divided warm doses. After two doses, high fever subsided, and the pulse was no longer rapid, but stool remained impacted. I then gave 3 qian of pure Mangxiao powder mixed with 1 liang of honey in boiled water. Defecation occurred, and the disease resolved.

Case 2: A young man suffered from exogenous excess heat causing dry constipation for over ten days. His pulse was rapid (>6 beats/respiration) and weak upon deep pressure. I prescribed Baihu Jia Renshen Tang, substituting Shengdihuang (Rehmanniae Radix) for Tianmu and Shengshanyao (Dioscoreae Rhizoma) for Jingmi. Decocted into a large bowl, taken in multiple small warm sips. After one dose, the rapid pulse slowed. I reduced the dose slightly and continued. I intended to continue until the pulse normalized before purging. Unexpectedly, after the second dose, defecation occurred spontaneously. The exogenous excess heat also completely dissipated. This effectively substituted Baihu Jia Renshen Tang for Chengqi Tang. Since curing this case, whenever a purgative indication exists but can be treated gently, I often substitute Baihu Tang or Baihu Jia Renshen Tang for Chengqi Tang. Their cooling, moistening, and descending power often slowly resolves dryness, allowing natural defecation without Chengqi Tang, eliminating fears of unresolved disease or collapse.

Case 3: A young woman contracted Cold Damage after extreme anger. Heat transmitted to Yangming, causing dry constipation. Two prescriptions of Dachengqi Tang were vomited up. Her pulse was wiry, long, and forceful. A wiry-long pulse indicates blazing Liver Fire regardless of location, explaining the rejection of the medicine. I reduced Houpo and Zhishi in Dachengqi Tang (to 1.5 qian each), added 1 liang of Shengbaishao (Paeoniae Radix Alba) and 1 liang of Shizhe Shi (Ochre Hematite). Before taking the decoction, she took 3 qian of Shizhe Shi powder with plain water to prevent vomiting. Three hours later, defecation occurred, and she recovered.

Case 4: A person habitually damaged by smoking and sexual indulgence usually had bowel movements every 7-8 days. Due to exogenous excess heat, he had not defecated for 16-17 days, with irritability and abdominal fullness. Enema expelled some dry stool, but symptoms persisted. Doctors cited Qi deficiency and weak pulse, fearing purgatives. I found his pulse weak but fire excessive. I prescribed Weitiao Chengqi Tang plus Yetaishen (Wild Codonopsis) 4 qian, Shizhe Shi 8 qian, and Tiandong (Asparagi Radix) 8 qian. Decocted into a large bowl, taken in three warm sips. After two sips, the abdomen rumbled, indicating opening. He stopped after the third sip. Two hours later, defecation occurred, internal heat vanished, and he recovered instantly.

Two more cases illustrate situations where defecation occurred only after taking other medicines following failed Chengqi Tang attempts.

Famous local doctor Liu XX: When I was learning medicine, he often visited my home. One day, I saw him treating a case of Cold Damage with heat entering Yangming and dry constipation. Previous doctors had given two doses of Dachengqi Tang without success. Dr. Liu prescribed only 3 qian of Weilingxian (Syringae Ramulus) decocted in water. Defecation occurred, and the disease resolved. I asked: Weilingxian can promote urination and defecation, but its purgative power is far inferior to Xiao and Huang. Why did 3 qian work where Dachengqi Tang failed? He replied: There is subtle logic. The previous two doses of Dachengqi Tang remained in the abdomen. Due to temporary stagnation of Zang-Fu Qi transformation, the drug power paused. Weilingxian's penetrating power triggered this stored power, causing the stalled Xiao and Huang to suddenly exhibit their purgative nature, leading to defecation. Weilingxian acts like a fuse for Xiao and Huang. Hearing this profound theory, I gained great insight and successfully applied this method subsequently.

Huox XX from a neighboring village: Contracted Cold Damage after anger-induced Liver Fire. Abdominal fullness and dry constipation for 7-8 days. Dachengqi Tang failed to induce defecation, causing unbearable pain in the hypochondrium. Left pulse was deep, wiry, and forceless, indicating Liver Qi stagnation and fire excess. I urgently prescribed 3 qian Chaihu (Bupleuri Radix) and 1 liang ShengMaiya (Hordei Fructus Germinatus). Decocted and taken. Half an hour later, hypochondriac pain ceased. Over an hour later, defecation occurred. Abdominal fullness disappeared, and the disease resolved completely.

This case follows the previous logic, borrowing power from prior medications. The Kidney governs the gate of the two excretions. The Liver moves Kidney Qi and governs dispersion. Bowel movement depends on the Liver. Regulating Liver stagnation promotes defecation. Chaihu regulates the Liver by ascending, while ShengMaiya regulates by dispersing and unblocking. Using only Chaihu might worsen hypochondriac pain initially. Together, they harmonize Liver Qi, opening stagnation and restoring dispersion. *Shennong Bencao Jing* states Chaihu treats knotting Qi in the heart, abdomen, and intestines, food accumulation, and alternating chills and fever, pushing out the old and bringing forth the new. Repeated reading confirms Chaihu not only regulates the Liver but also reduces fullness and promotes defecation. Although Chaihu is not a descending purgative, it assists Xiao and Huang in promoting defecation. Conversely, in cases of Spleen-Stomach Qi sinking with diarrhea, combined with Renshen and Baizhu, it lifts Spleen-Stomach Qi to stop diarrhea. Chaihu is indeed a miraculous herb. Those skilled in using it deeply understand its subtleties.

For pregnant women with exogenous excess heat and dry constipation, Chengqi Tang can be used, as stated in *Neijing*: "If there is a cause, there is no harm." However, careful judgment is required...