TCM Skin CompendiumEducational reference

Comparison

Dang Gui Yin Zi vs Xiao Feng San

Both are classical formulas for itchy skin, and both are built around the idea that Wind drives the itch. They are often confused because both disperse Wind and both nourish Blood. In the library they sit on opposite sides of one decision: is the skin dry and depleted, or red, damp and moving? This page compares what Dang Gui Yin Zi and Xiao Feng San record.

How to use this comparison. This is a reading aid, not a recommendation: formula choice depends on the whole person and belongs with a qualified practitioner. Read the full pages, especially their safety sections, and use Start here, the glossary and the pattern self-check when a term is unfamiliar.

At a glance

What the library records for each formula
Dang Gui Yin ZiXiao Feng San
Composition focus Blood nourishment first: Dang Gui, Sheng Di Huang, Bai Shao, Chuan Xiong and He Shou Wu, with the gentle Wind herbs Ji Li, Fang Feng and Jing Jie, plus Huang Qi and Gan Cao to help the surface hold moisture. Four jobs at once, with Blood nourishment as protection: Wind herbs Jing Jie and Fang Feng with Niu Bang Zi and Chan Tui; Heat herbs Shi Gao, Zhi Mu and Ku Shen; Dampness herbs Cang Zhu and Mu Tong; and Dang Gui with Sheng Di Huang for the Blood.
Pattern it treats Blood Deficiency with External Wind Wind-Heat, acting with Dampness on a Blood base that is not quite sufficient
Skin picture Dry, rough, finely scaly skin on a pale, depleted person. The itch is persistent and worse at night or in bed, and scratching makes it rougher. Itchy, red and weeping skin. The itch moves, lesions ooze clear fluid or crust, and warmth and stress make both worse.
Signs that separate them Pale or dull complexion, a papery surface, tiredness, a pale tongue and a thin pulse. Bright redness, oozing and crusting, a red tongue with a yellow greasy coat, and itch that worsens in heat.
Main cautions Avoid where Damp-Heat dominates with heavy oozing and a red greasy tongue. Contraindicated in pregnancy, and Dang Gui and Chuan Xiong may add to anticoagulant and antiplatelet medication. Avoid pale, cold skin from Cold or Yang deficiency, which cooling and drying herbs would worsen. Care in weak digestion; caution in pregnancy; Gan Cao may interact with antihypertensives, diuretics and blood-sugar-lowering medication.

What each formula is for in skin practice

Dang Gui Yin Zi: rebuilding what the skin is missing

The Dang Gui Yin Zi page describes a formula for dry, rough, scaly skin that itches worse at night on a pale, depleted person. Blood moistens the skin, so when Blood is low the surface dries and the dryness is said to generate the Wind that itches. The formula rebuilds the Blood and settles the Wind together, which is why it is classed as a nourishing formula rather than a clearing one. The skin is thin and dry rather than wet, and the page puts improvement over weeks.

Xiao Feng San: taking Wind, Heat and Dampness out of the surface

The Xiao Feng San page describes a formula for skin that is itchy, red and weeping. Wind makes the itch move, Heat reddens it, Dampness makes it weep, and Blood nourishment is included so the drying does not leave the skin rough. Hives that come and go, a contact reaction, a mild drug rash and the early weeping stage of eczema all share this picture. Bright redness, oozing and crusting, and itch that worsens in warmth distinguish it from the dry picture.

The distinguishing signs

  • Dry versus damp. Dang Gui Yin Zi is for a dry, rough, scaly surface; Xiao Feng San is for one that oozes, weeps or crusts. Oozing is the clearest practical difference, and it is why Dang Gui Yin Zi is excluded when Damp-Heat dominates.
  • Depletion versus excess. The first treats a lack of substance, so the person tends to look pale and tired. The second treats factors that have to be cleared, so there is visible inflammation, warmth and congestion.
  • Pale versus red tongue. The Xiao Feng San page notes that the tongue decides between them, pale pointing one way and red with a yellow coat pointing the other. That continues the logic of Blood Deficiency with External Wind and Wind-Heat.
  • Night itch versus heat-triggered itch. The depleted picture is worse in bed under the covers; the Wind-Heat picture is worse in warmth and under strain through the day.
  • Chronic versus acute. Dang Gui Yin Zi is recorded for the chronic depleted phase, improving over weeks. Xiao Feng San is used for an acute flare for one to two weeks, or four to eight weeks when subacute or recurring, with reassessment.

Where they overlap

The two formulas share Dang Gui, Sheng Di Huang, Jing Jie, Fang Feng and Gan Cao, and both treat moving itch as a Wind sign. Both include Blood nourishment and both are written for itchy conditions that can run for weeks. That shared ground is why the reference record compares them directly, and why the tongue and the state of the skin decide more than the disease name.

How a practitioner might choose

Read together, the pages give this logic. Where the skin is dry, pale and thin, the itch is worse at night, the person is depleted and the tongue is pale, the picture fits Blood Deficiency with External Wind and Dang Gui Yin Zi is the formula the library records. Where the skin is red and weeping, the itch moves, warmth makes it worse and the tongue is red with a yellow coat, the picture fits Wind-Heat and Xiao Feng San is the recorded choice.

The exclusions matter as much as the match, and both pages describe a course that is reviewed rather than continued indefinitely. This page sets out the comparison; the formula and safety pages hold the detail.

Conditions each appears in

Dang Gui Yin Zi

  • Atopic dermatitis: dry, itchy skin on a pale, depleted base rather than red and weeping.
  • Breast eczema: chronic dry itching where the general picture is Blood deficiency.
  • Anal irritation: persistent dry itch without discharge or heat signs.
  • Athlete's foot: only the dry, scaly, non-weeping late stage, not the acute damp-heat flare.

Xiao Feng San

  • Contact dermatitis: red, itchy, sometimes weeping reactions with heat and wind signs.
  • Drug rash: only for mild itchy red eruptions, and only alongside medical advice, because a drug reaction can be serious.
  • Breast pruritus: itchy red skin where the pattern is Wind-Heat with Dampness.
  • Burning hot skin to the touch: heat with itch and redness rather than dryness.

Modern references

PubMed records relevant to the modern, non-TCM discussion of these formulas, plus general herbal safety reviews. They are references, not proof that either formula treats a skin condition.