Cold and Fever During Your Period, Then Nighttime Raving and Unconsciousness? Doctor Xu Shuwei Treats Heat Entering the Blood Chamber

Patient search terms: cold or flu during your period / fever while menstruating / period fever / unconscious after a cold / talking nonsense at night / rattling throat phlegm / can’t catch your breath / period started then stopped

Medical terms for this condition: heat entering the blood chamber (re ru xue shi) · cold damage (shang han) · shaoyang pattern · phlegm clouding the heart orifices

Opening: a sister lies unconscious, her throat rattling like a saw

Today we continue the stories of Doctor Xu Shuwei, the master of classic formulas (jingfang), treating patients with the methods of Zhang Zhongjing’s Shang Han Lun — and the phrase we need to learn this time is re ru xue shi — heat entering the blood chamber.

In the second month of the year 1131 (xinhai in the old calendar), in Piling — the region around today’s Changzhou — there lived a school official named Wang Zhongjing. A school official in those days was the sort of civil servant who ran local teaching and examinations. And that name sounds familiar, doesn’t it? Zhongjing — as in Zhang Zhongjing, the sage of Chinese medicine! Doctor Luo jokes that Wang’s parents must have hoped he would study medicine when they named him, but he never did — he became an education official instead.

His sister fell ill with cold damage (shang han). By the seventh or eighth day, she was deeply unconscious: her eyes closed, and no matter who called her, she would not wake. From her throat came a loud, rattling gurgle of phlegm, as harsh as a saw cutting wood. The illness had become truly critical, and the family hurried to fetch Doctor Xu Shuwei.

💬 Note from Doctor Luo: Doctor Xu Shuwei (1079–1154), courtesy name Zhike, was a celebrated physician of the late Northern and early Southern Song dynasties, known as “Scholar Xu.” As a young man he sat the imperial examinations for many years, and by the time he finally passed at an advanced age he knew the senior examination officials well. He devoted himself to Zhang Zhongjing’s Shang Han Lun and excelled at its classic formulas. He left behind Ninety Cases on Cold Damage — the earliest surviving case-record book in Chinese medical history: one case, one discussion, recording his own treatments in meticulous detail.

Doctor Xu does not rush to write a prescription — first he asks, “What symptoms came before?”

When Doctor Xu arrived, he did not dash off a formula. Instead he questioned the family carefully about the history of the illness.

First he asked: “Had she shown any symptoms like this before, while she was still unmarried?” Her mother answered: “On the fourth or fifth day of this illness, she began talking nonsense at night, as if she had seen ghosts” — raving in the dark, answering nobody, speaking to some invisible presence in the air. Terrifying, the mother said.

💬 Note from Doctor Luo: Mark this detail! Talking nonsense at night is what Chinese medicine calls zhanyu — delirium. It is an enormously important clue: fine during the day, but every night it returns. The illness has its own rhythm. The moment Doctor Xu heard this, he had already guessed seven or eight parts of the diagnosis.

The key question: “Did this happen to fall right at the start of your period?”

Doctor Xu then asked one more question, and it was the question of a master:

“At the very beginning of the illness — had her period just come?”

The mother’s eyes lit up: “Yes — exactly!” Her daughter’s period had begun just as the fever struck (jing shui shi lai) — and then, the moment the cold damage took hold and her body heated up, the period stopped dead.

Doctor Xu now had the answer: this was heat entering the blood chamber.

What is heat entering the blood chamber? Zhang Zhongjing wrote it out long ago

The term “heat entering the blood chamber” was set down explicitly by Zhang Zhongjing in the Shang Han Lun:

In a woman with wind-strike fever, if her period has just come, she is clear-headed by day but delirious at dusk, and the episodes come at set times — this is heat entering the blood chamber.

Clear by day, raving at night, with episodes that follow a rhythm — that is the classic signature of heat entering the blood chamber.

So how does the illness actually happen? Doctor Luo breaks it down:

💬 Note from Doctor Luo: When a pathogen enters the body, the outermost line of defense is the Taiyang channel. If that defense fails, the pathogen moves deeper into the Yangming channel, where the body fights back fiercely with high fever. If Yangming also falls, the pathogen enters the Shaoyang channel. Shaoyang is paired with the liver and gallbladder — and in a woman, the uterus and reproductive system are precisely along the pathway of the liver channel. When the pathogen follows the liver and gallbladder channels down into the uterus and stirs up heat there, that is heat entering the blood chamber.

Why does it always seem to happen during a period? Because when menstruation comes, the qi and blood of the uterus are left empty — the pathogen slips in through the opened door, tangles with the blood, and blocks the channels. That is why the period so often stops abruptly (though sometimes it dribbles on). When there is heat in the blood level, daytime fever mostly follows the qi level, but at night the yin and blood take charge, and the heat disturbs the spirit upward — so the woman raves at night. Remember this: the single most important sign of heat entering the blood chamber is talking nonsense at night.

The previous doctor’s mistake: warm tonics stuffed the chest full of phlegm

With the mechanism this clear, you would think the treatment was easy. But the doctor who had treated her before did not recognize heat entering the blood chamber — and, following the usual habit, gave her warm, tonifying medicines.

That was a disaster. The warm tonics fed the heat, the chest and diaphragm tightened and clogged (xiong ge bu li), phlegm surged upward in waves, and the patient began wheezing for air, her breathing rapid and shallow (chuan cu xi gao). She was worse than ever.

Doctor Xu took one look and said: the heat in this illness has reached its extreme (bing re ji yi). At this moment you cannot rush to clear the heat from the blood chamber — you must first dissolve the phlegm stuck in her throat and bring the heat down, or the person cannot be saved.

First move: Yi Xia San dissolves the phlegm and opens the orifices — four hours later she wakes

Doctor Xu reached for the old formula Yi Xia San (One-Haze Powder): tian nan xing (arisaema) as the leading herb to dissolve phlegm, paired with bai jiang can (white stiff silkworm) and quan xie (whole scorpion) to dissolve phlegm and extinguish wind — the classical emergency formula for coma with overwhelming phlegm, when life hangs by a thread.

💬 Note from Doctor Luo: Remember this combination — arisaema with white stiff silkworm and whole scorpion — it is made for the critical emergencies where turbid phlegm is so heavy the patient is unconscious. Phlegm blocks the throat and veils the clear orifices, so the person sinks into coma; dissolve the phlegm, let the breath move again, and the person wakes.

And so it happened: four hours later the phlegm gradually cleared, and the patient fell into a natural sleep. When she woke, her senses had returned — no longer comatose, she was aware of the world again.

Second move: Xiao Chaihu Tang plus sheng di huang — three doses, fever gone, sweat breaks

With the phlegm dissolved, the next task was to clear the residual heat from the blood chamber. Doctor Xu used Xiao Chaihu Tang (Minor Bupleurum Decoction) plus sheng di huang (raw rehmannia):

• Xiao Chaihu Tang (chai hu/bupleurum, huang qin/scutellaria, ren shen/ginseng, ban xia/pinellia, gan cao/licorice, sheng jiang/fresh ginger, da zao/jujube dates) — the formula Zhang Zhongjing designated for heat entering the blood chamber, drawing the pathogen outward through the Shaoyang level;
• Plus sheng di huang — with heat burning inside, the body fluids suffer most: patients tend to be dry-mouthed, red-tongued and restless. Sheng di huang nourishes yin, nourishes the blood, and generates fluids.

After three doses, the fever broke, she broke into a sweat, and the illness was resolved — completely cured.

💬 Note from Doctor Luo: Zhang Zhongjing gives another line: a woman with wind-strike who, seven or eight days in, has chills and fever at set times, whose period has just stopped — this too is heat entering the blood chamber, and her blood must be bound (qi xue bi jie), which is why she has attacks like malaria at fixed intervals — Xiao Chaihu Tang is the prescription (Xiao Chaihu Tang zhu zhi). If only sweat breaks out on the head alone (dan tou han chu) — heat pressing upward — you may instead needle the Qimen point (LR14) to drain the heat of the liver channel, and that cures it as well.

People today need to understand heat entering the blood chamber even more

Doctor Luo says this illness is still common today — and its range is actually wider than the ancients described:

💬 Note from Doctor Luo: It is not only menstruation. After childbirth, or after induced abortion or a surgical termination, the uterus is left empty of qi and blood, and a pathogen can slip in exactly the same way. Many gynecological conditions today — pelvic inflammatory disease, endometritis, salpingitis and ovarian inflammation, pelvic connective-tissue inflammation, puerperal infection — deserve a serious thought of heat entering the blood chamber when they show fever at set times, alternating chills and heat, a full and tight chest and flanks, dull lower-abdominal pain, or even night delirium.

When a girl catches a cold during her period, Xiao Chaihu Granules (the ready-made form of Minor Bupleurum Decoction) often work faster than anything else — precisely because the formula harmonizes Shaoyang and pushes the pathogen outward. Later physicians such as Doctor Xue Lizhai built on this foundation with flexible additions: herbs to clear heat and draw the pathogen out, herbs to nourish yin, herbs to nourish the blood (like dang gui and shao yao). Their experience grew richer, but the core remains Xiao Chaihu Tang — open the Shaoyang gate, push the pathogen out, and the illness resolves.

Studying Doctor Xu’s classic formulas is not about making everyone a jingfang expert. It is about mastering the way of thinking — so that when a family member or friend really meets this situation, you know in your heart: when Xiao Chaihu Tang is called for, do not let anyone patch the patient up with blindly warm tonics.

Compiled from Doctor Luo Dalun’s explanations of Doctor Xu Shuwei’s cases; the case comes from Ninety Cases on Cold Damage.