What Xuan Bi Tang is for
The skin over a joint is red, tight and shiny, and the joint beneath it is swollen. The whole limb feels heavy and the surface is hot to the touch. In some pictures the fingers or toes burn and redden, and the colour deepens when they are warm. The explanation is Damp-Heat lodged in the channels and the joint, and the formula drains the Dampness out while clearing the Heat rather than warming the area.
The redness here is full and even over the swelling, and the stretched skin has a sheen because the tissue beneath is tight with fluid. The joint is painful to move, the limb feels weighted, and humid weather makes it worse. It is an acute, hot presentation and it looks quite different from the pale, cool joint that eases with warmth. Where the toes or fingers burn and redden, the same Damp-Heat is showing at the surface.
Fang Ji and Yi Yi Ren drain the Dampness out of the channels and joints, and Fang Ji is the herb chosen for the hot swollen joint. Hua Shi and Chi Xiao Dou carry the Damp-Heat away through the urine, which is the exit this formula uses. Lian Qiao and Zhi Zi clear the Heat, Xing Ren opens the Lung Qi so fluids descend, Ban Xia dries the Dampness that has thickened, and Can Sha reaches the joint itself. The tightness and the shine reduce as the fluid moves.
Pale, cool, non-red joints that improve with warmth are a different pattern altogether, and the cold draining herbs would leave them worse. Because the formula is cold and draining, weak digestion needs care, and it is contraindicated in pregnancy. A hot swollen joint is also a medical matter until infection has been excluded, so the formula is used alongside assessment rather than instead of it.
Actions
- Clears Heat and drains Dampness
- Unblocks the channels and relieves obstruction
- Disperses swelling and relieves pain
- Promotes urination to drain Dampness
Properties
- Taste and temperature: Predominantly bitter and bland with some acrid quality. Bitter clears Heat and dries Dampness, bland promotes urination and drains downward, acrid opens the channels.
- Organs: Spleen, Lungs, Large Intestine, Bladder
- Channels: Spleen, Lung, Bladder, Large Intestine
The pattern behind it
The pattern is Damp-Heat lodged in the channels and joints. The Heat produces redness and heat, the Dampness produces swelling and heaviness, and together they obstruct the flow so the limb becomes painful and stiff. Draining the Dampness out and clearing the Heat removes both halves of the obstruction.
Composition
The herbs in Xuan Bi Tang, with their role and dose.
| Role | Herb | Dose | Properties | Why it is there |
|---|---|---|---|---|
| King | Fang Ji | 15 g | Cold, Bitter, pungent | Drains Dampness from the channels and joints and is used specifically for hot swollen joints. |
| King | Xing Ren | 15 g | Slightly warm, Bitter, sweet | Opens the Lung Qi so fluids descend and the Dampness has a route out. |
| Yi Yi Ren | 15 g | Cool, Sweet, bland | Drains Dampness and relaxes the sinews, easing the heavy stiff feeling. | |
| Hua Shi | 15 g | Cold, Sweet, bland | Guides Damp-Heat out through the urine. | |
| Lian Qiao | 9 g | Slightly cold, Bitter | Clears Heat and resolves toxin, reducing the inflammation. | |
| Zhi Zi | 9 g | Cold, Bitter | Clears Heat and drains it downward, supporting the urinary route. | |
| Ban Xia | 9 g | Warm, Pungent | Dries Dampness and transforms Phlegm where the Dampness has thickened. | |
| Can Sha | 9 g | Warm, Pungent, sweet | Reaches the channels and joints specifically, draining Dampness where it has settled. | |
| Chi Xiao Dou | 9 g | Neutral, Sweet, sour | Drains Dampness and clears Heat through the urine, supporting the drainage. |
Patterns it treats
Painful Obstruction due to Damp-Heat in Channels
Red, tight, shiny skin over a hot swollen joint, with a heavy limb and fingers or toes that burn. Damp-Heat lodged in the channels produces the swelling and the heat together, so the surface looks stretched and full rather than pale.
How the formula is built
The formula opens a route out and closes the source of heat at the same time. Fang Ji, Yi Yi Ren, Hua Shi and Chi Xiao Dou drain Dampness through the urine; Lian Qiao and Zhi Zi clear the Heat; Xing Ren keeps the fluids descending; Can Sha and Ban Xia reach the joints and the thickened Dampness. It is a draining formula rather than a warming one, which is why it is used for hot swollen limbs.
Skin conditions it is used for
Where this formula appears in the skin conditions of the library.
Preparation and use
Decocted in water and taken warm, in two divided doses.
Modifications
- If the Heat is marked, more cooling herbs are added.
- If the swelling dominates, more draining herbs are added.
- If pain is severe, Blood-moving and channel-unblocking herbs are added.
- For chronic cases, herbs supporting the Spleen and Kidney are added so the Dampness does not recur.
Timing
Taken warm in two divided doses.
Duration
One to two weeks for an acute flare, and four to eight weeks for chronic Damp-Heat obstruction with reassessment.
Diet while taking it
Avoid alcohol, greasy and sweet food; reduce salt if there is swelling.
Safety
Contraindications
Avoid in cold-type obstruction: pale, cool, non-red joints that improve with warmth. Avoid in pregnancy. Use care in weak digestion because the formula is cold and draining.
Interactions
The draining herbs can add to diuretic medication. Fang Ji requires care because of its toxicity profile, and it is used only under professional supervision.
Pregnancy
Contraindicated. Ban Xia is classified as a pregnancy-caution herb in traditional texts, and Fang Ji raises separate concerns.
Breastfeeding
Use only under professional guidance.
Children
Used only with professional supervision.
Before you use it
Recorded from the classical record and rewritten in this project's own words. Educational only: not a prescription, and a hot swollen joint needs medical assessment to exclude infection.
General safety references
General references for herbal hepatotoxicity and herb-drug interactions; they are not specific to this formula.
- Review article: Herbal hepatotoxicity - an update on traditional Chinese medicine preparations. Alimentary Pharmacology & Therapeutics, 2014. PMID: 24844799.
- Interactions between herbal medicines and prescribed drugs: an updated systematic review. Drugs, 2009. PMID: 19719333.
- Warfarin and food, herbal or dietary supplement interactions: a systematic review. British Journal of Clinical Pharmacology, 2021. PMID: 32478963.
Origin and history
Wen Bing Tiao Bian (温病条辨, Systematic Differentiation of Warm Diseases) by Wu Jutong, Qing dynasty, 1798.
Wu Jutong recorded the formula in 1798 in his treatise on warm diseases, at a time when Damp-Heat was increasingly recognised as a distinct cause of joint and channel disease. Its draining approach contrasted with the warming classical obstruction formulas, and that is why it is used for the hot swollen limb rather than for the cold fixed joint.
Classical record
The formula is recorded in the warm-disease tradition for painful obstruction caused by Damp-Heat in the channels, with swollen painful joints and a greasy tongue coat
Wen Bing Tiao Bian (温病条辨, Systematic Differentiation of Warm Diseases), Wu Jutong, Qing dynasty, 1798.
Evidence note
No controlled trial of this treatment in skin conditions was identified for this entry. What is described here rests on the classical and later materia medica record and on traditional clinical use, not on controlled trial evidence, and it is not a prediction of benefit. Where skin-specific research does exist it is linked above.
Common questions
How is it different from Juan Bi Tang?
Juan Bi Tang disperses Cold-Wind-Dampness and tonifies. Xuan Bi Tang drains Damp-Heat and is cooling, so the two treat opposite patterns: hot swollen versus cold fixed joints.
Is it safe with a hot swollen joint?
A hot swollen joint needs medical assessment first to exclude infection or acute arthritis. This formula may then be used alongside that care.
Why does it contain Lung-opening herbs?
Opening the Lung Qi helps fluids descend, which gives the Dampness a route out through the urine rather than letting it settle in the joints.
How long is it used?
One to two weeks for an acute flare, and longer for chronic Damp-Heat obstruction with reassessment.