Common Cold with Chills and Shivering? Doctor Zhang Xichun Treated Dual Cold Invasion of Tai Yang and Shao Yin with the Mahuang Fuzi Xixin Tang (Ephedra, Aconite, and Asarum Decoction)
Opening: in the middle of summer, he took a nap — and woke up shivering with cold
It was a midsummer noon in Tianjin. Li Ruzhai, thirty-two years old, a director of the Shandong Bank, was young and promising, in the prime of his strength. At lunch he ate his fill of ice-cold melon and fruit, happy and satisfied; on top of that, he had slept badly the night before, so after the meal he fell into a deep sleep. Who could have imagined that when he woke up, something serious had happened.
💬 Note from Doctor Luo: Many friends see the words “external contraction” or “cold damage” and assume it has nothing to do with them. In fact, the way Chinese medicine treats external-contraction disease is the same whether we are talking about meningitis, Japanese encephalitis, COVID-19, or an ordinary cold — the reasoning is identical and the formulas are much the same. If you learn these principles, then when you really do catch a cold with a high fever, you will know how to handle it — the White Tiger Decoction and raw gypsum we discussed in the previous article are exactly this line of thinking.
Who was the patient? Three “modern diseases” piled onto one person
Li Ruzhai’s illness had a chain of causes, one link after another — a textbook case. First, he ate a great deal of cold melon and fruit — the spleen and stomach were chilled first. Then, he had been sleepless the night before and had not rested properly. During the nap he dreamed, and in the dream he had a nocturnal emission — and with that, his kidney qi was weakened too. To make matters worse, the weather suddenly changed, and a gust of cold wind blew over him and woke him. When he woke, his whole body was cold and trembling — he shivered and shook all over, and there was a vague pain deep in his belly: all that cold fruit he had eaten was now coming to “settle the account.”
💬 Note from Doctor Luo: Look at this — these three causes are really the vices of modern people: loving cold food, which chills the spleen and stomach; air conditioning and dressing too lightly, which exposes the body to cold; and insufficient kidney qi — and nowadays there are far too many people with deficient kidney qi. Doctor Zhang Xichun never picked his cases at random; this one was aimed straight at modern people.
The patient himself was frightened out of his wits: his whole body was cold, he had had a nocturnal emission in his dream, and his belly hurt — this was serious! He hurriedly sent for Doctor Zhang Xichun. To be able to call in Zhang Xichun in those days was a stroke of luck.
One feel of the pulse: all six positions faint, almost gone — Zhang Xichun’s verdict on the spot
When Zhang Xichun arrived, he first took the pulse: all six positions were fine and faint, almost imperceptible (liu bu jie wei xi yu wu). Combining that with the shivering all over and the pain in the abdomen, Zhang Xichun knew exactly what he was dealing with: this was cold damage striking the shao yin channel directly (zhi zhong shao yin zhi shang han) — precisely the pattern for the Mahuang Fuzi Xixin Tang (Ephedra, Aconite, and Asarum Decoction).
💬 Note from Doctor Luo: The Mahuang Fuzi Xixin Tang treats dual cold invasion of tai yang and shao yin (tai shao liang gan) — the tai yang and shao yin channels are invaded at the same time. Tai yang is the first line of defense, at the surface of the body; shao yin is the kidney channel, in the very depths of the body. When the outermost defense line catches cold and the innermost kidney is chilled as well, that is dual cold invasion. Such patients are, as a rule, people whose kidney qi was already insufficient. What did Zhang Zhongjing say in the Treatise on Cold Damage (Shang Han Lun)? “When shao yin disease first begins, if there is contrary fever and a deep pulse (shao yin bing shi de zhi, fan fa re mai chen zhe)…” — note that word “contrary” (fan): a genuine shao yin disease does not produce fever, because the body no longer has the strength to resist. The fact that this patient still ran a fever meant the tai yang channel at the surface was still fighting back — that is the tai yang manifestation; and the deep pulse meant kidney qi was insufficient — that is the shao yin manifestation. One “contrary fever” plus one “deep pulse” together make dual cold invasion.
So why did Li Ruzhai have no fever, only shivering? Zhang Xichun’s explanation is brilliant: in an ordinary case of dual invasion with fever, the fever shows the body still has the power to resist. This patient, however — first the cold melon and fruit injured the tai yin spleen channel, then the nocturnal emission injured his kidney qi — inside and out all was cold, and the tai yang surface did not even have the strength left to fight. Hence only shivering, no fever. When treating illness you must be flexible; do not cling rigidly to the words “must have fever.” Understanding the principle is what matters.
💬 Note from Doctor Luo: If shao yin disease goes a step further — as resistance declines further — you see the classic signs of diarrhea with undigested food (xia li qing gu), cold hands and feet (shou zu jue ni), and a constant desire to sleep (dan yu mei) — always drowsy and listless. In my experience, many patients who fit the Mahuang Fuzi Xixin Tang pattern are dismissed as “mild cases,” yet during the day they are always drowsy and short of energy — this is actually very common. The reason is that on the whole their yuan qi (original qi) is insufficient and their resistance has begun to decline, leaving only a little fight left. So this formula pattern should be understood from the angle of “the body’s resistance is insufficient.”
Breaking down the prescription: three herbs as the base, plus Zhang Xichun’s own “trump card”
Zhang Zhongjing’s original formula has just three herbs: Mahuang (ephedra) releases the exterior and helps disperse the cold pathogen from the surface; Fuzi (aconite) warms the interior and rouses the body’s yang qi — when yang qi is faint and resistance is insufficient, you use Fuzi to stir the body awake so it can fight; Xixin (asarum) also warms yang, but its most special function is unblocking (tong) — the formula would still work without it, but with it the whole body warms up almost immediately after drinking. That is the warming-and-unblocking action of asarum.
💬 Note from Doctor Luo: The doses in this formula are all modest: Mahuang is usually used at 6 g, Xixin at 3 g — the old saying “xixin bu guo qian” (asarum never more than one qian) refers to taking it as a powdered preparation; in a decoction it is quite safe, and many modern practitioners use asarum at 6 g. For Fuzi, 9 g of the prepared herb is enough — of course, doctors of the Fire Spirit (huo shen) school will use tens or even a hundred grams. When I use this formula myself, I sometimes add a little gan jiang (dried ginger), and the effect is especially good — basically one or two doses can turn the illness around. If you use it on your own, 3 g of Mahuang is plenty, and honey-prepared Mahuang is even more stable.
On top of the formula, Zhang Xichun added several more herbs — and this is the most thought-provoking part of the whole case. He saw that Li Ruzhai’s problem was not only insufficiency of kidney yang, but insufficiency of kidney essence (jing) — after a nocturnal emission, the kidney qi was certainly depleted. So he added shu di huang (prepared Rehmannia), 1 liang (about 30 g), to nourish the kidney essence. He added sheng huai shan yao (raw Chinese yam), 5 qian (about 15 g) — the cold melon and fruit had injured the spleen and stomach, so the tai yin spleen channel was affected too; Chinese yam supplements the spleen. And he added jing yu rou (mountain cornel, shan zhu yu), 5 qian (about 15 g), to supplement the essence of the heart and liver.
💬 Note from Doctor Luo: Prepared Rehmannia, Chinese yam, and mountain cornel — these three are the principal herbs of the Liu Wei Di Huang Wan (Six-Ingredient Rehmannia Pill) and the Jin Gui Shen Qi Wan (Kidney Qi Pill from the Golden Cabinet), and they are also the three most important herbs Doctor Zhang Xichun used to treat deficiency conditions — whenever he supplemented deficiency, he almost always used these three. They were his trump card. Prepared Rehmannia paired with warming herbs supplements in the direction of kidney yang; paired with yin-nourishing herbs it nourishes the true yin — a wonderfully versatile herb. Huai shan yao means the genuine medicinal yam from Wen County, Jiaozuo, Henan — another of Zhang Xichun’s trump cards. People’s constitutions today are not what they used to be: when I use the Mahuang Fuzi Xixin Tang, I use Chinese yam at around 30 g, because there are so many people with insufficiency.
Next he added gan jiang (dried ginger), 3 qian (about 9 g) — it helps Fuzi warm the yang, and also helps the Chinese yam warm the spleen yang, because this man had eaten so many raw cold fruits that deficiency of spleen-stomach yang was the main cause of his illness. Dried ginger alone was not warm enough, so he added gong ding xiang (clove) — clove warms the yang. The everyday clove-and-cinnamon navel plaster (ding xiang, rou gui qi tie) — herb powder placed in the navel — warms exactly the yang of the spleen and kidney.
Two refinements in the decoction method: boil the ephedra first and skim the foam; sip slowly in small amounts
Zhang Zhongjing was very particular about the decoction method: take one dou of water, first boil the ephedra, reduce it by two sheng, and skim off the foam floating on top (yi shui yi dou, xian zhu mahuang, jian er sheng, qu shang mo) — boil the ephedra alone first, let off part of the water, remove the foam from the surface, and only then add the other herbs. Why? If the foam is not removed, drinking the ephedra can cause palpitations (xin huang) — ephedra is a stimulant, and people with irregular heartbeats or heart problems must be especially careful with formulas containing it. If you follow Zhang Zhongjing’s method and boil off the foam first, the rate of palpitations drops dramatically.
💬 Note from Doctor Luo: Even after the foam is removed, do not gulp down a whole big cup at once — some people’s hearts cannot take it. Drink one small cup, watch the reaction, then drink another small cup — that way it is steady and safe. In clinical practice there really are cases of reckless prescribing where the patient went home and drank the whole thing at once and suffered terrible palpitations. Everyone should be careful.
Zhang Xichun’s instructions to Li Ruzhai: decoct to one large cup, drink it hot, wrap yourself in clothes to let out a little sweat — but he cautioned “do not let it go too far” (wu ling guo du).
The result: drank it once — an hour later, the illness was gone
Everyone should remember: sweating is not the goal — it is not true that the more you sweat, the more thoroughly the pathogen is expelled. Sweating is a sign that the body has become warm inside and the channels are open, so a light sweat appears. Once you start to sweat, stop taking the medicine — continuing to force sweat will actually injure the upright qi. Li Ruzhai drank this single dose, and about an hour later, a light sweat covered his body and the chills and shivering stopped completely — he drank it once, and the disease was cured.
💬 Note from Doctor Luo: Zhang Xichun’s diagnosis was spot on — he saw at once that this was a direct strike on the shao yin channel, and his choice of herbs was precise, so one dose cured it. He was truly a master. This case also teaches us an old saying: “cold damage tends to kill those whose lower origin is deficient (shang han pian si xia xu ren)” — among people who catch the same external-contraction epidemic, those who end up critical and die are mostly the ones with deficient kidney essence. Why? Their vitality is not flourishing, their resistance is low. Look at the people struck down in the pandemic: their tongue coating is often thick and greasy, the tongue body pale — the yang qi is suppressed. The ones who died were mostly elderly people with insufficient kidney qi. These are all warnings.
A bonus life lesson: why is kidney qi so easily depleted?
Doctor Luo Dalun sums up the three great reasons modern people’s kidney qi becomes insufficient. First, indulgence — night after night of revelry is a drain, and being addicted to watching videos also secretly consumes kidney essence. Second, staying up late — staying up late also consumes kidney essence; some people think, “I haven’t indulged in anything, so why am I kidney deficient?” — but staying up late every single night drains you just the same. Third, excessive worry and rumination (si lü guo du) — thinking about too many problems, having too many desires, demanding and pursuing things all day long — all of these consume kidney essence.
💬 Note from Doctor Luo: I once had a friend ask me to look at his tongue, and I told him his kidney qi was deficient. He was astonished: “My wife and I have been separated for years — how can my kidney qi be deficient?” I asked him: do you like staying up late? He said that because of work he had basically never slept normally. So you see — staying up late, ruminating, and indulging are all roads that drain kidney essence. When kidney yang is insufficient, the body enters a cold, deficient state, and in a cold, damp, yin environment it easily catches external pathogens. Then, like this patient, if you habitually eat ice-cold fruit and drink ice-cold beer, the cold-damp inside you is heavy — and when the weather outside turns cold, the external pathogen slips in through the weakness, and dual cold invasion arrives.
Studying this case is not about sending everyone out to write prescriptions. It is about learning the principle of Chinese medicine — and the principle of Chinese medicine is the principle of life itself: keep your kidney qi supplemented day to day, touch cold melon and fruit less, protect the yang of the spleen and kidney, and keep your upright qi sufficient — then even when cold arrives, it will not strike your shao yin channel directly. And if you do fall ill before you have managed to adjust yourself, at least you can hold the master’s way of thinking in your mind as a reference — and know clearly which direction to go.
Based on Doctor Luo Dalun’s explanation of Doctor Zhang Xichun’s medical case; the case is from the Records of Chinese Medicine with Western Reference (《医学衷中参西录》).