Black Stool and Mania? What to Do When Someone’s Stool Turns Black and He Starts Raving — Song Dynasty Formula Master Xu Shuwei Cures Cold Damage Blood Stasis and Mania With Di Dang Tang (Leech and Gadfly Decoction)

Patient search words: black stool / dark stool / mania and agitation / going crazy / forgetting things easily / poor memory / hard full lower abdomen / yellowish skin

Corresponding medical terms: blood stasis pattern (yu xue zheng) · blood stasis bound in the lower burner (xia jiao zhu xue) · blood stasis · Di Dang Tang pattern (di dang tang zheng)

The opening: every other doctor wanted to “stop the mania” — but Doctor Xu Shuwei held them back

Today we continue the stories of Doctor Xu Shuwei, the great formula master of the Song dynasty. Doctor Xu Shuwei was a celebrated physician of the transition between the Northern and Southern Song dynasties. Known by his courtesy name Zhike and honored as “Scholar Xu” (Xu Xueshi), he studied Zhang Zhongjing’s Shang Han Lun (Treatise on Cold Damage) with extraordinary devotion, excelled at the classical formulas, and wrote Discussion of Ninety Cases of Cold Damage (Shang Han Jiu Shi Lun) — the earliest surviving case-record monograph in Chinese medical history. One case, one discussion: he recorded the illnesses he personally treated with complete clarity.

Today’s case opens with a consultation — and a dramatic one. The patient was already raging and out of control, and the other doctors had agreed to “stop his mania” with iron powder (tie fen) and ox gallstone (niu huang) — the medicine was already prepared. Doctor Xu Shuwei took one look and held them back: “Fei qi zhi ye” — “That is not the correct treatment.” The way you are treating him is wrong!

💬 Note from Doctor Luo: Doctor Xu Shuwei was always like this — after other physicians had made their diagnosis, he would stand against the general opinion and immediately point out the truth. It is a bit like solving a case: everyone else had it wrong; he looked once and found the real culprit — “you judged incorrectly; you have wronged this man.” This case begins exactly with that “fei qi zhi ye.”

Who was the patient? Mo Ziyi: after seven or eight days of typhoid, the man suddenly “went crazy”

The patient’s name was Mo Ziyi (a name recorded phonetically). He had contracted shang han — cold damage, an externally contracted illness. After seven or eight days of illness, Doctor Xu felt the pulse and found it mai wei er chen — faint and deep: very weak, needing firm pressure to be felt at all. That word “deep” (chen) carries real significance — we will come back to it in a moment.

Then the symptoms — three of them stood out sharply:

• Shen huang — yellow body: the skin had turned yellow, a rather deep shade.
• Fa kuang — mania: the mind was affected; he was raging and restless, as if deranged.
• Shao fu ying man — hard, full lower abdomen: the lower belly was distended; when he lay flat and someone pressed on it, it was hard, tense and bulging, and firm pressing brought pain.

💬 Note from Doctor Luo: Put these three together, and in Chinese medicine this is called the blood stasis pattern (yu xue zheng). Notice Doctor Xu’s diagnostic thinking — he did not fixate on the mania and try to stop it. Instead he first hunted for the root cause of the mania. That way of thinking is extremely important.

Pressing the belly: the “abdominal examination” invented by Zhang Zhongjing — treasured by Japan’s Kampo school

In this case, pressing the belly is the decisive diagnostic move. Doctor Xu did not spell it out, so Doctor Luo adds a detail for everyone: in this kind of blood stasis patient, when you touch below the navel it is cold — icy cold — because the qi and blood are not flowing there.

💬 Note from Doctor Luo: Do you know who invented “pressing the belly” as a diagnostic method? Zhang Zhongjing. Zhang Zhongjing paid extraordinary attention to the belly: when seeing a patient he always pressed the abdomen; every different sensation in the belly had its own meaning. This abdominal examination later spread to Japan, where there is now the Kampo (han fang) school — doctors who use Chinese formulas — and they treat abdominal palpation as a diagnostic tool of prime importance, comparable to our tongue diagnosis and pulse taking. When seeing a patient they always press the belly. Where did that come from? Straight from Zhang Zhongjing.

Why were the earlier doctors wrong to stop the mania with iron powder and ox gallstone?

Why did the earlier physicians want to use iron powder and ox gallstone? Because they reasoned: the patient is raving — heat toxins have invaded the heart channel and the mind-spirit is disturbed. If toxins attack the pericardium and heart channel, a person becomes manic. On that logic, iron powder and ox gallstone would settle the fright and calm the spirit, stopping the raving.

💬 Note from Doctor Luo: The iron powder has its own pedigree. The Huang Di Nei Jing (Yellow Emperor’s Classic of Internal Medicine) contains only thirteen formulas in the whole book, and one of them is Sheng Tie Luo Yin (Decoction of Raw Iron Filings) — the iron filings that fly off and scatter when a blacksmith strikes iron, ding-ding-dang. Once cooled, this substance has a calming, spirit-settling action; boiled in water it settles the spirit. So using iron powder was not reckless — it had a classical basis. But Doctor Xu Shuwei said: no, this is not the root of the illness.

Doctor Xu saw the truth: this illness was a blood stasis pattern (yu xue zheng). Those four characters carry enormous weight.

The blood stasis pattern: Zhang Zhongjing was the first to write down clearly “how to treat blood stasis”

Friends, the phrase “blood stasis” — we hear it constantly today: the body is blocked, there is stagnant blood. But have you ever asked: where did this whole method of treating blood stasis, this whole way of differentiating the pattern, come from?

💬 Note from Doctor Luo: Let me tell you: it was Zhang Zhongjing who set it out, in the Shang Han Lun. Zhang Zhongjing opened up a great many treatment methods, with exceptionally clear understanding of pathology and disease mechanisms — he truly opened the way for later generations. The concept of blood stasis already existed in the Huang Di Nei Jing — the Nei Jing contains abundant discussion of impeded blood circulation — but it was in Zhang Zhongjing’s work that the treatment of blood stasis was first clearly established, formulas included. Because the Nei Jing contains no formulas — no prescriptions for blood stasis. Zhang Zhongjing’s formulary — Tao He Cheng Qi Tang (Peach Kernel Decoction to Order the Qi), Di Dang Tang (Leech and Gadfly Decoction), Gui Zhi Fu Ling Wan (Cinnamon Twig and Poria Pill) — these are not one formula but several! From that point on, humanity knew how to resolve blood stasis. That is a truly extraordinary achievement.

Doctor Xu Shuwei, in making his diagnosis, also cited what Zhang Zhongjing said. He said: Zhongjing yun: in cold damage illness, the body is yellow, the pulse is deep and bound (mai shen jie), and the lower abdomen is hard (shao fu ying). A deep pulse means there is stasis and obstruction, so the pulse becomes deep and bound; a hard lower abdomen — that is the shao fu ying man we described: the patient himself feels the distension, and when the doctor presses, the dominant sensation is “hard” — very hard to the touch; press further down and it hurts inside. This is the sign of blood stasis (yu xue zhi zheng).

Then comes Zhang Zhongjing’s crucial second sentence: “Xiao bian bu li zhe, wei wu xue ye” — if the urine does not pass freely, then there is no blood stasis; the blood is insufficient, and at that point you cannot yet resolve stasis. “Xiao bian zi li zhe” — if the urine passes freely and normally, it shows the blood is still adequate — “qi ren ru kuang zhe, xue zheng di ye” — then if such a person is frenzied like this, it is a true blood-level illness, certain proof of blood stasis.

Zhang Zhongjing’s original text: freely passing urine is actually the evidence of blood stasis?

Here is a particularly interesting detail — take note: the patient’s urine passed freely, even more than usual (xiao bian fan li). Normally, when stasis is bound in the lower burner, urine should be scanty and difficult to pass. Yet this patient passed urine abundantly and normally.

💬 Note from Doctor Luo: Why? Zhang Zhongjing explains it clearly: “Tai yang sui jing, yu re zai li” — the tai yang channel is followed and heat and stasis accumulate within. When an external pathogen arrives, it is in the tai yang channel — what we call the tai yang pattern: the disease is at the body surface of tai yang, connected with channels and organs. The foot tai yang bladder channel: when an external pathogen arrives, it very easily travels along the channel into the bladder — this is “sui jing” (following the channel). So the illness “follows the channel and accumulates in the bladder” — it collects at the bladder, which is why his belly below the navel is distended — that is why the lower abdomen is hard, full, and painful on firm pressure. And where exactly is the blood stasis? In the lower burner. The external pathogen is at the lan men — the lan men is the junction between the small and large intestines — where it can seep into the large intestine and genuinely produce stasis inside. So: urine passing freely, lower abdomen hard and full, the person raving — xue zheng di ye: the evidence is conclusive.

So what is to be done? Zhang Zhongjing said: Di Dang Tang may be used. Doctor Xu Shuwei followed Zhang Zhongjing’s method and gave him Di Dang Tang (Leech and Gadfly Decoction).

Di Dang Tang is given: black blood comes out, the mania stops, a sweat breaks and the illness resolves

After the medicine, the prescription was given twice, and blood was passed several times (xia xue shu ci) — what does “moving blood” mean here? It means the stagnant blood was expelled either through the urine or through the stool. The blood that came out was black in color. Once the stagnant blood was out, the mania stopped (kuang zhi) — the raving state came to an end; a sweat broke and the illness resolved (de han er jie). And that is how he was cured.

After this case, Doctor Xu also quoted the Huang Di Nei Jing: “Jing yun: xue zai xia ze kuang, zai shang ze wang” — “the Classic says: blood below causes mania; blood above causes forgetfulness.”

💬 Note from Doctor Luo: If stagnant blood sits in the lower part of the body, the person tends to become manic; if it sits in the upper part, the person tends to forget things — poor memory. What does this show? Blood stasis in different parts of the body can both give rise to mental and emotional problems. This is a rough generalization, of course, but later generations have always taken this rule seriously.

Why is the stool black? Blood stasis and bleeding are often a pair

Why is the blood that comes out black? Because a person with blood stasis often has “stasis and bleeding at the same time” — stagnant blood and active bleeding frequently combine.

💬 Note from Doctor Luo: Think of a river: when the downstream is blocked, water cannot pass; the blockage grows worse, and upstream the river overflows its banks — where there is blood stasis, there is often bleeding as well. Fresh blood is bright red, but as it travels slowly through the intestines and mixes with the stool, over time the color turns black. So people with blood stasis often have very dark stools — black stool is itself a diagnostic clue, indicating there is bleeding inside. And when medication dissolves and expels the stagnant blood, the blood expelled is likewise often black. So remember this: when the stool turns black, do not only think of digestive-tract bleeding — also consider blood stasis.

How does blood stasis arise? Cold, qi deficiency, heat, blood deficiency, and anger

Having finished the case, Doctor Luo widens the discussion: what exactly is blood stasis? Blood stasis is an obstruction of blood circulation — the blood is blocked somewhere, and we call that stasis. The causes are numerous:

• Cold can cause blood stasis — cold makes the blood congeal and stagnate;
• Qi deficiency (qi xu) can cause blood stasis — deficient qi lacks the strength to propel the blood;
• Excess heat can also cause blood stasis — the blood is “dried out” by heat; the fluids are evaporated away. Zhang Zhongjing’s pattern here is heat: the heat pathogen enters the body, the body fights it, heated blood accumulates in certain places, qi and blood movement is obstructed, and the blood gets stuck there;
• Blood deficiency (xue kui) — when the blood is insufficient it cannot circulate properly and may form a blockage somewhere;
• Qi stagnation (qi yu) — anger produces all kinds of bindings, which can likewise produce blood stasis.

What does a person with blood stasis look like? Ten signs — check yourself against them

Doctor Luo says this is the day’s real lesson — the symptoms of blood stasis. Zhang Zhongjing described blood stasis with exceptional clarity; combining his lines with the summaries of later generations, here is a “blood stasis self-check list”:

First, a faint and deep pulse (mai wei er chen). Zhang Zhongjing said “in tai yang disease of six or seven days, if the exterior pattern is still present and the pulse is faint and deep.” Later generations described the pulse of a blood stasis patient as like “qing dao gua zhu — a light knife scraping bamboo”: a rough, impeded feel; you must press down to find it. This is one of the signs of blood stasis.

Second, the mind is affected — mild cases forget easily, severe cases rave. Why does blood stasis affect the mind? The heart governs the blood vessels, and it also governs the spirit (xin zhu xue mai, you zhu shen ming). When somewhere in the body is blocked, the heart’s function suffers; when the heart’s spirit-governing function suffers, the mind goes wrong. Mild cases show shan wang — forgetting easily. Zhang Zhongjing says later: “Qi ren xi wang zhe, bi you yu xue” — “a person who is habitually forgetful must have blood stasis” (in the yang ming pattern).

💬 Note from Doctor Luo: Do you know anyone like this in daily life — forgets things easily, forgets in the blink of an eye? Manic people are not common in ordinary life, but people who forget easily are extremely common! Zhang Zhongjing said, “in the yang ming pattern, a person who is habitually forgetful must have blood stasis” — a long-standing disturbance of blood circulation, stagnant blood inside, and that is why he forgets. So a very large proportion of people who forget things easily and have poor memory actually have blood stasis — their blood circulation is poor. Everyone, please remember this one.

Third, localized pain. Wherever there is blood stasis, there is pain: stasis in the arm or leg — swelling and pain in the limb; stasis in the chest — pain in the chest; stasis in the lower abdomen — a hard, full lower belly that hurts on pressure. A reaction at the local site of the lesion is a sign of blood stasis.

Fourth, black stool. As explained above: stasis and bleeding together, and the stool turns black.

Fifth, dry throat. A person with blood stasis will have a dry throat and mouth, always wanting to rinse the mouth with water — but not wanting to drink, because he is not actually thirsty.

Sixth, dark lips. The lips of a blood stasis patient turn black and dull, with a blue-purple darkness around the mouth.

Seventh, dark circles under the eyes. Some people develop dark circles around the eyes.

Eighth, very dry skin. The skin shows “ji fu jia cuo” — skin like fish scales: in winter it is extremely dry, like fish scales, flaking at the lightest touch.

Ninth, visible red threads. On the legs and body there are various blood threads, raised capillaries.

Tenth, the tongue. The blood stasis tongue: stick out the tongue, and the edges may show petechiae and ecchymotic spots (yu ban, yu dian) — patches of black spots, and looking closely you see black dots; curl the tongue upward, and the veins under the tongue are engorged (she xia jing mai nu zhang) — normally two faint, barely visible lines, but in a blood stasis patient they bulge, black and thick, like coral branches.

💬 Note from Doctor Luo: Note that in Zhang Zhongjing’s time these things were recorded, but the tongue signs had not been summarized this clearly. Later generations kept summarizing, following Zhang Zhongjing’s line of thought, and discovered many more indicators of blood stasis. Check yourself against this list — if these apply to you, consider whether you may have blood stasis.

Two more of Zhang Zhongjing’s lines: eating a lot yet not passing stool is also blood stasis

After the indicators, Zhang Zhongjing has two more lines specifically about judging blood stasis — Doctor Xu Shuwei quoted these as well:

Line one: The patient has no exterior or interior pattern (wu biao li zheng) — neither exterior nor interior signs remain — and has had fever for seven or eight days; although the pulse is floating and rapid (mai fu shu), it may still be purged; suppose the purge has already been done, yet the rapid pulse does not resolve (mai shu bu jie) — the heart still beats fast — and “he re ze xiao gu shan ji” — the heat combines and the person becomes exceptionally hungry, eating constantly, never full on anything; “zhi liu qi ri bu da bian zhe, ci you yu xue ye” — if to six or seven days there is still no bowel movement, this is blood stasis, and Di Dang Tang is appropriate.

Line two: In cold damage with heat, the lower abdomen is full (shao fu man) — the lower belly is distended; the urine should be scanty (ying xiao bian bu li) — by rights the urine should be hard to pass; but now it passes freely (jin fan li zhe) — this is blood (wei you xue ye); it should be purged downward, leaving no medicine behind (dang xia zhi, bu ke yu yao).

💬 Note from Doctor Luo: Remember these two lines: xiao gu shan ji (being exceptionally hungry), no bowel movement for six or seven days, together with lower abdomen full while urine passes freely — all of these are evidence of blood stasis. The “xiao gu shan ji” line especially: many people think being able to eat a lot is a good thing, but “eating constantly, still hungry, and never passing stool” can be blood stasis at work. Zhang Zhongjing wrote every symptom out with complete precision. A doctor is a doctor — truly remarkable.

What is hidden inside Di Dang Tang? Leech, gadfly, peach kernel, and rhubarb

For a patient like Mo Ziyi who has already gone manic, this is the severe form of blood stasis bound in the lower burner (xia jiao zhu xue zhi zhong zheng) — the stasis is very serious. What is used? Di Dang Tang.

First, a word on the name. Where does “Di Dang Tang” come from? There are various explanations:

💬 Note from Doctor Luo: The late Doctor Liu Duzhou said that “di dang” was another name for the leech — an alternate designation of shui zhi — hence the name Di Dang Tang. My own understanding: Di Dang Tang simply means “the decoction that opens the blocked path” (tong yu tang). How so? In modern Chinese “di dang” (抵挡) is one word meaning “to resist, to hold back”; but in ancient times there was no such compound — each character carried its own meaning: “dang” (挡) means to block, to obstruct; “di” (抵) means to push through — to force something aside, to shove it, like an ox horn pressing hard against something; “di da” (抵达) means to arrive; a sword “zhi di” (直抵) to his throat means penetrating, reaching. So what does “Di Dang Tang” mean? Push the obstructing thing away — like “di,” shove the obstacle out of the way. I think that interpretation makes good sense.

The composition of Di Dang Tang: the first two ingredients are extraordinary — shui zhi (the leech) and meng chong (the gadfly) — both animal medicines.

Shui zhi — the leech. The leech contains hirudin, which has a blood-dissolving action — it breaks up congealed blood.

💬 Note from Doctor Luo: Leeches — I saw them often as a child in the northeast. In the streams and ditches near the rice paddies not far from home they were everywhere: stretching and contracting, growing very long when extended, short when bunched up. The moment one touched an animal it latched on and sucked — it contains blood-dissolving substances, rapidly breaks up your blood and draws it in, swelling up quickly. The leech is a blood-sucking animal with an exceptionally powerful blood-dissolving action — it can even cross the blood-brain barrier. Ordinary drugs cannot cross the blood-brain barrier, but hirudin can get through to dissolve stagnant blood, with excellent results. Essentially any ordinary blood stasis it can break up. I have told you before about Tong Xin Luo capsules (Capsules for Unblocking the Heart Channels) — lately many people have heart problems, blood stasis, chest tightness and pain. Tong Xin Luo is made by Yiling Pharmaceutical — the company that makes Lianhua Qingwen — and in fact this company rose to prominence on Tong Xin Luo; Lianhua Qingwen came much later. The first ingredient in Tong Xin Luo is ren shen (ginseng) — to tonify the qi; the second ingredient is shui zhi, the leech — and what is it for? To dissolve the stagnant blood.

Meng chong — the gadfly. The gadfly is the horsefly that flies in the air — also a bloodsucker: it bites a cow and the blood is drawn out. Why can it draw blood? Because it too has blood-dissolving action, breaking up congealed blood. Leech and gadfly — these are the first two ingredients of Di Dang Tang.

Tao ren — peach kernel. The first two are animal medicines with great force; the peach kernel is an herb, and it resolves tangible blood stasis. Zhang Zhongjing said: remove the skin and tips, use 20 kernels.

Da huang — rhubarb. To complete the formula, rhubarb. Here rhubarb does three jobs at once: purges downward, drains heat, and resolves stasis (tong xia, xie re, hua yu) — because heat and blood stasis are bound together, the cold purging (han xia) method is used to flush the stagnant accumulation out of the intestines.

💬 Note from Doctor Luo: Pay attention to how rhubarb is used: normally rhubarb is added late (hou xia) — if you want it to purge downward, adding it late works best; if it is decocted with the other ingredients from the start, rhubarb’s heat-clearing action comes to the fore. Here Zhang Zhongjing wanted both the purging action and the heat-clearing, stasis-resolving action, so he handled it with great care. And how was the decoction taken? Warm, one sheng at a time (wen fu yi sheng) — boil three sheng, first take one sheng warm, then watch whether blood is passed; if not, continue with the rest. There is also the alternative form Di Dang Wan (Leech and Gadfly Pill) — leech, gadfly, peach kernel, and rhubarb made into pills; pills act more gently, taken little by little.

Closing: blood stasis is the great enemy of cardiovascular and cerebrovascular disease

At this point Doctor Luo reflects: this case is one of the earliest standardized case records of treating the blood stasis pattern in the whole of Chinese medical history.

💬 Note from Doctor Luo: Zhang Zhongjing opened the way, writing down how to treat blood stasis and with which formulas. But how were his formulas actually used afterward? At first, later generations were not entirely sure. By the Tang dynasty, even the incomparable Sun Simiao, the King of Medicines, wanted to see the Shang Han Lun and could not: he said “Jiang nan zhu shi mi Zhongjing zhi fang er bu chuan” — “the physicians of the Jiangnan region secretly kept Zhongjing’s formulas and would not pass them on” — some doctors south of the Yangtze had Zhang Zhongjing’s formulas but simply refused to transmit them, which is infuriating. Only in his old age did Sun Simiao finally see the text, and he treasured it like a priceless gem. From the Tang through the Song dynasties, case records multiplied, and Doctor Xu Shuwei was the earliest case-record master to apply the Shang Han formulas — he wrote Discussion of Ninety Cases of Cold Damage, showing everyone exactly how the formulas should be used. This is, in fact, one of the earliest case records on treating blood stasis — from now on, whenever anyone speaks of blood stasis or Di Dang Tang, Doctor Xu’s case will be cited.

Doctor Luo continues: when I talk about blood stasis today — in every health lecture I give, blood stasis comes first, and sometimes it takes up half the entire talk. Why? Because people with blood stasis are extremely numerous, and the harm of blood stasis is extremely great: today’s cardiovascular and cerebrovascular diseases, the various nodules and tumors — blood stasis is severe in all of them; in late-stage diabetes, necrosis of the extremities and retinal hemorrhage are also linked to blood stasis. The number-one cause of death in our country, cardiovascular and cerebrovascular disease, is in fact, to a large degree, blood stasis.

💬 Note from Doctor Luo: So this is a vast subject, and I hope everyone will learn more about it. Master this material well and it is of real value for protecting your own health and your family’s health — who knows, after forty or fifty, cardiovascular problems, heart trouble, rising blood pressure — most of these are tied to blood stasis. How to prevent and treat blood stasis? That is tomorrow’s topic. Today we will stop here — see you tomorrow!

What to take away

• Black stool is not only a sign of digestive bleeding — it can also point to blood stasis. Because blood stasis and bleeding often occur together, stagnant blood expelled from the body is frequently black; a person with blood stasis often passes dark stools.
• Mania and forgetfulness can both come from blood stasis. As the Nei Jing put it: “blood below causes mania; blood above causes forgetfulness.” Mild blood stasis shows up as forgetfulness and poor memory — a very common sign; severe blood stasis can drive a person to raving.
• Zhang Zhongjing’s formula for severe blood stasis is Di Dang Tang (leech, gadfly, peach kernel, and wine-washed rhubarb) — animal medicines that dissolve congealed blood, with rhubarb purging heat and stasis downward. It is a strong formula for a strong pattern; Doctor Xu Shuwei’s case of Mo Ziyi is one of the earliest standardized records of its use.
• A useful blood stasis self-check: deep faint pulse, forgetfulness, localized pain, black stool, dry throat with no real thirst, dark lips, dark circles under the eyes, fish-scale-dry skin, visible blood threads, ecchymotic spots at the tongue edges, and engorged dark veins under the tongue.
• Blood stasis has many roots — cold, qi deficiency, heat, blood deficiency, and anger — so the treatment differs by cause; protecting your heart and blood vessels from an early age means keeping blood moving and preventing stasis from building up.

Compiled from Doctor Luo Dalun’s commentary on Doctor Xu Shuwei’s case records; the case is from Discussion of Ninety Cases of Cold Damage (《伤寒九十论》, Southern Song dynasty, by Doctor Xu Shuwei).