What Si Wu Xiao Feng Tang is for
This is the formula for chronic dry, itchy skin that scales and thickens on a depleted base, where the itch persists after an eruption has settled and is worse at night or in dry weather. It nourishes the Blood that the itch has consumed and disperses the Wind that keeps it active, so the skin is fed and calmed at once.
The skin is dry, rough and scaly, and it thickens where it has been scratched. The itch moves about rather than staying in one place, the plaques can look like psoriasis or pityriasis rosea, and the skin between them is pale and dry. It is worse at night or in dry weather, and it continues after the original eruption has settled. The surface is under-nourished and irritable rather than hot, wet or spreading.
Dang Gui, Sheng Di Huang, Chi Shao and Chuan Xiong nourish and move the Blood so the skin is fed and the nourishment reaches the surface. Jing Jie, Fang Feng, Chan Tui, Bo He and Du Huo disperse the Wind that drives the moving itch, and Bai Xian Pi clears the mild Heat behind any redness. Chai Hu reaches the half-exterior, and Da Zao supports the Blood and the middle. Nourishing alone would leave the itch, and dispersing alone would dry the skin further, so both are given together.
It belongs to the persistent, dry phase, not to the acute hot weeping stage, where the skin is red, wet and spreading and needs a different approach. The very depleted person needs more tonic support than this formula gives on its own. Taken for weeks while the skin settles, it is a nourishing and dispersing formula rather than a strong one, and persistent or worsening skin disease needs medical assessment.
Actions
- Nourishes and moves Blood
- Dispels Wind and stops itching
- Clears Heat
- Supports the skin's recovery
Properties
- Taste and temperature: Predominantly sweet and pungent with a bitter note. Sweet nourishes Blood, pungent disperses Wind, bitter clears Heat and dries.
- Organs: Heart, Liver, Lungs
- Channels: Heart, Liver, Lung
The pattern behind it
The pattern is Blood deficiency with Wind and mild Heat. The thin Blood cannot nourish the skin, so it dries and itches; Wind keeps the itch moving; and mild Heat keeps it red. The formula nourishes the Blood and disperses the Wind, which is why it is used for chronic dry itch rather than for the acute weeping phase.
Composition
The herbs in Si Wu Xiao Feng Tang, with their role and dose.
| Role | Herb | Dose | Properties | Why it is there |
|---|---|---|---|---|
| Sheng Di Huang | 9 to 12 g | Cold, Sweet, bitter | Cools the Blood and nourishes Yin, addressing the dryness and mild heat. | |
| King | Dang Gui | 6 to 9 g | Warm, Sweet, pungent | Nourishes and moves Blood, the leading tonic of the formula. |
| Jing Jie | 4.5 to 6 g | Slightly warm, Pungent | Dispels Wind and settles the itch. | |
| Fang Feng | 4.5 to 6 g | Slightly warm, Pungent, sweet | The standard Wind herb for itch and weather sensitivity. | |
| Chi Shao | 3 to 6 g | Slightly cold, Bitter | Cools and moves Blood, supporting the circulation of the nourishing herbs. | |
| Chuan Xiong | 3 to 6 g | Warm, Pungent | Moves Qi and Blood so the nourishment reaches the skin. | |
| Bai Xian Pi | 3 to 6 g | Cold, Bitter | Clears Heat and relieves itch, used for chronic itchy skin conditions. | |
| Chan Tui | 3 to 6 g | Cold, Sweet, salty | Disperses Wind and clears Heat while easing itch. | |
| Bo He | 3 to 6 g | Cool, Pungent | Disperses Wind-Heat lightly and clears the head. | |
| Du Huo | 2 to 3 g | Slightly warm, Bitter, pungent | Dispels Wind-Dampness and reaches the lower body, broadening the action. | |
| Envoy | Chai Hu | 2 to 3 g | Slightly cool, Pungent, bitter | Reaches the half-exterior and helps vent the pathogen. |
| King | Da Zao | 4 to 6 dates | Warm, Sweet | Nourishes the Blood and the middle, supporting the tonic side. |
Patterns it treats
Blood Deficiency with External Wind
Chronic dry, scaly, thickened skin that itches, worse at night or in dry weather, and continues after an eruption has settled. The surface is under-nourished and irritable rather than hot or weeping.
How the formula is built
Four herbs nourish the Blood and eight disperse Wind and clear Heat, with Da Zao supporting the middle. That ratio is the formula's character: it is a nourishing base with enough Wind-dispelling to settle a chronic itch, which is why it can be taken for weeks.
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 dryness dominates, the Blood-nourishing herbs are increased.
- If the itch is severe, the Wind-dispelling group is increased.
- If Heat is marked, more cooling herbs are added.
- If the person is very depleted, further tonic support is added.
Timing
Taken warm in two divided doses.
Duration
Typically two to six weeks for subacute and chronic skin conditions, reassessed as symptoms evolve.
Diet while taking it
Avoid drying food: alcohol, fried food and heavy spice. Moistening and nourishing food supports the treatment.
Safety
Contraindications
Caution in Wind-Dampness or Wind-Cold patterns with strong external signs, where a dispersing formula alone is needed. Avoid in the acute hot weeping phase.
Interactions
The Blood-moving herbs may add to anticoagulant effects. Chai Hu and Bo He are generally mild.
Pregnancy
Use with caution in pregnancy. Chuan Xiong is a Blood-activating herb that promotes circulation.
Breastfeeding
Use only under professional guidance.
Children
Used in children with reduced dose for chronic dry itch.
Before you use it
Recorded from the classical record and rewritten in this project's own words. Educational only: not a prescription, and persistent or worsening skin disease needs medical assessment.
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
Recorded in the Qing surgical tradition as a modification of Si Wu Tang with Wind-dispelling and Heat-clearing herbs.
The formula developed in the Qing surgical tradition by combining the four-substance Blood tonic with the Wind-dispelling group used for itch. That combination addresses the two things chronic itch involves: the Blood that has been consumed and the Wind that keeps the itch active.
Classical record
The formula is recorded in the Qing surgical tradition as the four-substance decoction with Wind-dispelling and Heat-clearing herbs, for chronic itchy skin with dryness and depletion.
As recorded in the classical record for this formula.
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 Dang Gui Yin Zi?
Dang Gui Yin Zi is more nourishing, for the dry pale depleted itch. This formula adds more Wind-dispelling and Heat-clearing, so it is used when the itch is more active with some redness.
Can it help psoriasis?
For chronic dry plaques on a Blood-deficient base it can be part of the treatment. Psoriasis needs medical management, especially if extensive or affecting the joints.
Why are there both tonic and dispersing herbs?
Because chronic itch both consumes Blood and is driven by Wind. Nourishing alone leaves the itch, and dispersing alone dries the skin further.
How long is it used?
Two to six weeks typically, reassessed as symptoms evolve.