Tree barks and root barksHeat-clearingAilanthi Cortex

Chun Pi (Heaven Ailanthus Root - bark or Bark)

Q: What are the composition and effects of Chunpi?

Chunpi is pharmacopoeial Ailanthus altissima (Mill.) Swingle. It is bitter and astringent, cold in nature, and enters the Large Intestine, Stomach, and Liver meridians. Its functions are to clear heat and dry dampness, astringe and stop leukorrhea, stop diarrhea, and stop bleeding, and it is used for red and white leukorrhea, damp-heat diarrhea and dysentery, chronic diarrhea and dysentery, bloody stools, and flooding and spotting.

Q: What is the dosage of Chunpi? Can it be used daily as a leukorrhea-stopping tea?

A common decoction dose is 6 to 9 g, but modern use requires physician-determined dosage. It is not a year-round "Chunpi tea." Prolonged use may further injure spleen-stomach deficiency cold, and leukorrhea use should be short-term and medically guided.

Q: What are the contraindications of Chunpi? Can pregnant women use it?

Chunpi is not suitable for spleen-stomach deficiency cold. Pregnant women require physician evaluation. Stop use if loose stools or abdominal pain occur, and seek immediate medical care for severe leukorrhea or high fever.

Q: Can Chunpi clear heat, stop leukorrhea, and stop diarrhea?

It can help with red and white leukorrhea, damp-heat diarrhea and dysentery, chronic diarrhea and dysentery, bloody stools, and flooding and spotting. It clears heat and dries dampness, astringes and stops leukorrhea, stops diarrhea, and stops bleeding, but it is not a specific remedy for all leukorrhea or all diarrhea and dysentery.

Q: Can Chunpi be taken daily as a leukorrhea-stopping or diarrhea-stopping tea?

Damp-heat leukorrhea may be used short-term in formulas, but spleen-stomach deficiency cold can be worsened. The idea that Chunpi must stop leukorrhea cannot replace evaluation, and clearing heat and stopping leukorrhea requires physician-determined formulation and dosage.

Q: How to choose between Chunpi, Baitouweng, Huangbai, Qianshi, and Jinyingzi?

Chunpi clears heat and astringes leukorrhea, Baitouweng clears heat and stops dysentery, Huangbai clears heat and dries dampness, Qianshi benefits the kidney and secures essence, and Jinyingzi secures essence and reduces urine. Choose Chunpi for stopping leukorrhea, Baitouweng for stopping dysentery, Huangbai for drying dampness, Qianshi for securing essence, and Jinyingzi for reducing urine; pattern differentiation still applies, and large doses of Chunpi are contraindicated in spleen-stomach deficiency cold.

A practical guide to Chun Pi: what it is, how Traditional Chinese Medicine uses it, the classical formulas it appears in, and who should be careful with it.

View Herb Profile →

Last reviewed Oct 28, 2026

Quick Facts

Latin Name	Ailanthi Cortex
Chinese Name & Pinyin	椿皮 · Chun Pi
Medicinal Part	Tree barks and root barks
The item	Chun Pi is the dried root or trunk bark of Ailanthus altissima. Xiang Chun (Chinese toon) bark is a look-alike, not this herb. The bran-fried form is the common household-prepared piece.
Nature and channels	Cold, bitter, and astringent. Enters the Large Intestine and Liver. Cold bitter astringent clears damp-heat and tightens discharge, bleeding, and diarrhea.
Pharmacopoeia line	Clears heat and dries dampness. Astringes and holds. Stops discharge, bleeding, and diarrhea. Traditionally used for damp-heat vaginal discharge, bloody stool, chronic diarrhea, and intestinal bleeding.
Pattern cues	Heavy yellow thick discharge. Sticky bowel with burning anus. Blood in the stool. Chronic diarrhea with residual heat.
In this article	Chun Pi versus Huang Bai. Why astringency matters. Why the bran-fried form is gentler. Why pregnancy and cold-deficient stomach need caution. Who should skip it — cold-limbed, loose-stool, clear-discharge constitutions.

What Is Chun Pi?

Chun Pi (椿皮; Chūn Pí; Latin: Ailanthus altissima; English: tree-of-heaven bark) in the current pharmacopoeia is the dried root bark or trunk bark of the tree of heaven, gathered in spring or autumn, with the coarse outer layer removed and sun-dried. The common processed form is Chao Chun Pi, stir-fried with bran to soften its bitter-cold nature. It is cold in nature, bitter and astringent in taste, enters the Large Intestine and Liver channels, and its core actions are to clear heat and dry dampness, and to astringe and hold — stopping discharge, bleeding, and diarrhea. It is usually decocted as a bark piece. The usual amount is 6–9 g. It needs no special decoction method. The bran-fried form is gentler on the stomach than the raw bark.

It is not Huang Bai. Huang Bai is bitter and cold, purely draining lower-jiao damp-heat and fire, with no astringent hold; Chun Pi is bitter and astringent, clearing damp-heat while tightening discharge, bleeding, and loose bowel. It is not Xiang Chun bark. Chinese toon bark smells fainter, is more fibrous, and lacks the bitter-astringent taste. Cold, bitter, and astringent, it should not be used by a cold-deficient spleen and stomach — cold limbs, loose stools, abdominal coldness get worse. Clear, thin, whitish vaginal discharge with cold signs is a poor match. Pregnancy and breastfeeding should check with a practitioner first. Heavy bleeding, abdominal pain, or bloody stool with worsening symptoms need a clinic first; do not handle it on your own.

It is used most often for three patterns:

Damp-heat downward flow: heavy, yellow, thick vaginal discharge, possibly with itching and lower abdominal fullness
Intestinal damp-heat: blood in the stool, diarrhea with sticky bowel and burning anus — seek care
Chronic diarrhea or dysentery with residual damp-heat

Cold, bitter, and astringent, it is not a daily "tightening bark" to keep taking. Astringing when there is no damp-heat, in a cold weak stomach, traps cold and damages spleen yang.

When damp-heat pours into the lower jiao, or intestinal heat causes discharge and bleeding, Chun Pi is cold, bitter, and astringent. It clears damp-heat while holding what should be held, which is why it appears in Gu Jing Wan–type and Chu Pi San–type formulas. It clears and holds at the same time. A cold spleen and stomach, with no heat, get worse if more is added.

Chun Pi is not a catch-all astringent bark. In deficiency-cold, with clear thin discharge and loose stools, or in pregnancy, using it alone is a poor match. Whether it belongs in a formula, and whether raw or bran-fried, should be decided by a licensed Chinese medicine practitioner after pattern diagnosis.

Chun Pi: Materia Medica Profile

Identification & Quality Standard

Ailanthi Cortex

Botanical Origin

The dried root bark or trunk bark of Ailanthus altissima (Mill.) Wingle (Simaroubaceae).

Production Regions

Primarily produced in northern China and Zhejiang.

Quality Requirements

Superior medicinal material has lack rough skin and thick flesh, and yellowish-white inner surface.

Macroscopic Features

Root bark consists of uneven flat pieces or curled pieces, uneven length, 2~5(~10)mm thick; externally grayish yellow or yellowish-brown, rough, with obvious lenticels, longitudinally lengthened, slightly raised, sometimes the cortex has fallen off of the outer surface; pale yellowish-white; inner surface is pale yellow, relatively flat, with dense small fusiform holes or small spots. Firm and brittle texture; very fibrous fractured surface, the outer surface easily falls off. faintly oily odor that increases when broken; bitter taste. Trunk bark consists of board-shaped pieces, externally grayish-yellow or yellowish-brown; with irregular longitudinal and horizontal cracks, large lenticels, pale brownish-yellow when peeled; fractured surface is granular.

Where It Grows and How to Judge Quality

Chun Pi grows mainly in Shandong, Henan, Hebei, and Jiangsu, among others. Traditional sources and industry experience weigh some regions more, though quality also depends on variety, harvest timing, processing, and storage.

Good-quality Chun Pi usually looks like this:

Root bark as flat pieces or irregular rolled strips.
Gray-yellow to gray-brown outside, with irregular vertical wrinkles.
Pale-yellow to yellow-white inside, with fine vertical lines.
Hard and brittle, with an uneven, fibrous break, and a mildly bitter-astringent taste.

The processed Chao Chun Pi is yellowish on the surface, sometimes with a char spot, and smells mildly fragrant. Watch out for the look-alike Xiang Chun (Chinese toon) bark, which smells fainter and is more fibrous — its taste is clearly different from Chun Pi's bitter-astringency. Easy to tell apart with care.

Traditional Properties & Historical Lineage

Nature, Flavour & Channel Tropism

Bitter, Astringent; ColdLarge IntestineStomachLiver

1. What the Classics Recorded

Chun Pi has a clear paper trail in Chinese herbal literature. A few highlights:

Shen Nong Ben Cao Jing — listed it as a middle-grade herb, used for "driving out heat, stopping bleeding, and promoting urination."
Ming Yi Bie Lu — added its use for heavy menstrual bleeding and blood below, and cold pain in the belly.
Xin Xiu Ben Cao — noted it "stops diarrhea and thickens the intestines and stomach."
Ben Cao Gang Mu — said it "dries dampness, holds in, stops bleeding, and kills worms," used for blood dysentery, wind-intestine bleeding, hemorrhoids, and discharge.

2. How Views of the Herb Changed Over Time

Different generations of physicians read Chun Pi a little differently. Some stressed its astringent, holding role — for holding in leaking fluids, used for excess discharge and unending diarrhea. Others emphasized its clearing damp-heat role — for clearing intestinal and liver damp-heat, fitting heat-driven bleeding and yellow discharge. Still others narrowed its scope, warning that its cold nature means people with cold, weak digestion should use it with care, to avoid worsening the cold. These differences are not contradictions — they reflect different clinical scenes and a flexible reading of the herb.

This evolution is a good reminder of a core idea in traditional Chinese medicine: herbs are chosen to match the person, not just the symptom.

Core Efficacies & Traditional Applications

Traditional Functions

Clears heat and dries dampness, astringes and stops leucorrhea, stops diarrhea, stops bleeding.

1. Main Use One: Clearing Damp-Heat and Tightening Discharge

What it is: The first and most central use of Chun Pi is to clear damp-heat from the lower body (mainly the Liver and Bladder channels) and tighten excess discharge.

When it was used: Traditionally for damp-heat discharge — heavy, yellow, thick discharge, often with genital itching, a heavy lower belly, or sticky bowel habits and a burning back passage.

Common partners: Often paired with Huang Bai, Che Qian Zi, or Qian Shi — Huang Bai strengthens the lower damp-heat clearing, Qian Shi strengthens the holding effect.

Who should not self-use: People with thin, clear, pale discharge along with cold hands and feet and a cold belly — a cold-deficiency pattern — should avoid it on their own, since its cold nature may worsen the cold.

2. Main Use Two: Tightening Bleeding and Diarrhea

What it is: The second core use focuses on tightening the intestines' "sliding" state, clearing intestinal damp-heat while easing diarrhea and stopping blood.

When it was used: Traditionally for intestinal damp-heat bleeding — bright-red blood in the stool, or unending diarrhea with sticky stools and a burning back passage — also for long-lasting dysentery with residual damp-heat.

Common partners: Often paired with Di Yu, Huai Hua, or Huang Lian — Di Yu and Huai Hua strengthen the bleeding-stop, Huang Lian strengthens the intestinal damp-heat clearing.

Who should not self-use: People with cold, weak digestion — loose stools, a cold belly, cold hands and feet — or with dark-red blood and fatigue should avoid it on their own, since its cold nature may worsen the deficiency cold.

3. A Classic Pairing: Chun Pi and Huang Bai

A common pairing is Chun Pi with Huang Bai. Chun Pi is good at tightening discharge and clearing intestinal damp-heat; Huang Bai is good at clearing lower-body damp-heat and draining fire-toxin. Together they strengthen the damp-heat-clearing effect, while Chun Pi's astringency guards against Huang Bai's cold causing the intestines to "slide" — a fit for damp-heat-driven yellow discharge and sticky bowel habits.

Like most pairings, this should be matched to the person, not copied from a list. It belongs in the hands of a practitioner.

Modern Research

Modern research offers useful context, but Traditional Chinese Medicine prescribes on whole-pattern diagnosis rather than isolated compounds.

1. Main Chemical Compounds

Modern studies have detected several groups of compounds in Chun Pi:

Quassinoids — a signature group.
Alkaloids
Flavonoids
Terpenoids

One important point: detecting a compound in a plant does not mean that compound produces the same effect in the human body. Lab chemistry and human response are two different things.

2. Where Research Is Heading

Research so far is mostly at the early laboratory stage. What has been observed:

In test-tube experiments, the extract showed activity against some common intestinal bacteria, and some components reduced inflammatory-cell activity.
In animal studies, the extract appeared to help ease diarrhea in experimental mice.

These are promising early findings, not proven human benefits. Human clinical research has not yet confirmed a direct effect.

3. The Limits of Current Research

It is important to read the research honestly. Four limits stand out:

Lab results are not clinical results. Test-tube and animal findings happen under specific conditions and cannot be carried straight into human use.
Extracts are not the dried herb. An extract or single compound differs completely from the simmered dried slices in concentration and dose.
Doses and methods vary. Different studies use different extraction and dose, so results are hard to compare and no unified conclusion exists.
One compound is not the whole herb. Chun Pi works through many compounds together; a single ingredient cannot represent the whole effect.

Comparing Similar Herbs

1. What Chun Pi and Huang Bai Share

Huang Bai is the herb Chun Pi is most often compared with. They share quite a lot:

Both are traditionally used to clear lower-body damp-heat.
Both are used for damp-heat-driven discharge and sticky bowel habits.
Both need attention to constitution — people with cold, weak digestion should be cautious with both.

2. The Core Differences

Despite the similarities, the two herbs differ in a few practical ways:

Nature and taste: both are cold, but Chun Pi also carries an astringent taste while Huang Bai is purely bitter. The astringency gives Chun Pi a "clearing-and-holding" character, while Huang Bai's bitter leans to plain "clearing and draining."
Focus: Chun Pi clears damp-heat while tightening excess discharge, diarrhea, and bleeding — suited to damp-heat-driven "sliding." Huang Bai clears lower-body damp-heat and fire — suited to red, hot, swollen pain and scanty dark urine, with no marked holding effect.
Direction of action: Chun Pi tends to astringe, holding the intestine and lower body's fluids to stop sliding. Huang Bai tends to clear and drain, guiding damp-heat out downward, with no astringent role. Their qi-regulation directions differ completely.
Best fit: Chun Pi suits heavy, thick discharge or unending diarrhea with damp-heat. Huang Bai suits yellow discharge that is not too thick, scanty dark urine, and genital itching with red, hot, swollen pain — more of an excess damp-heat presentation.
Caution: Chun Pi is avoided for cold-deficiency thin discharge and unending diarrhea. Huang Bai is avoided for cold, weak digestion and for yin-deficiency heat with hot flashes and night sweats, since its bitter-cold may worsen yin-deficiency.

3. The Difference in One Sentence

Chun Pi leans more toward clearing damp-heat while holding in, while Huang Bai leans toward clearing damp-heat while draining fire. Both can be used for lower-body damp-heat, but they are not freely interchangeable.

Classical Formulas Containing Chun Pi

Gu Jing Wan

固經丸

Formula CategoryAstringent FormulasPrimary PatternYin DeficiencyPrimary FunctionEnrich Yin, clear Heat, stabilize menses, stop bleeding

View Formula Profile Read Complete Guide

Formulas vs. Single Herbs

A formula combines several herbs to create a whole effect. This is different from using a single herb in one key way:

Formulas are built as a whole — the pairing creates synergy or restraint that a single herb cannot.
A single herb cannot copy a full formula — without the other herbs, its effect falls off, and a single herb's bias may even cause discomfort.
Do not build your own formulas from online articles.

Diet & Daily Home Use

1. A Simple Home Tea: Chun Pi with Yi Mi and Fu Ling

A gentle, everyday way to meet Chun Pi:

Ingredients: about 5 g of Chao Chun Pi, 10 g of Yi Mi (coix seed), and 5 g of Fu Ling.
Method: soak the Yi Mi for 1 hour ahead, then simmer with Fu Ling in 500 ml of water for 20 minutes; add the Chao Chun Pi and simmer 5 more minutes, then take the liquid.
When it fits: summer damp-heat with heavy, thick discharge, or sticky bowel habits and a burning back passage — a light, everyday care.
Who should skip it: people with cold, weak digestion — cold hands and feet, loose stools.
Frequency: one to two times a week — not for long, continuous use.

Please note: Chun Pi is a dried medicinal herb, not an ordinary food. Confirm your pattern suits it before drinking regularly.

2. Dried Herb Decocting and Processing

The raw Chun Pi has a stronger bitter-cold nature — good for clearing damp-heat but more likely to hurt the stomach. The Chao Chun Pi is stir-fried with bran, softening the bitter-cold, and is better for home use. For a home decoction, place the Chao Chun Pi with the other ingredients in a pot (no special handling), cover with water, soak for 30 minutes, bring to a boil, then simmer on a low heat for 20 minutes.

Remember that different forms are not directly convertible — a prescription dose is set to the pattern, while a food-style dose is for light care; they cannot be swapped directly.

3. Dosage and How Long to Use

In traditional prescriptions, a common dose of Chun Pi is about 6 to 9 g, adjusted to the pattern. The food-style dose is smaller — about 5 g in the tea above.

Chun Pi is not meant for long-term, continuous use, because its cold nature may hurt the spleen-stomach yang over time. Pregnant women, nursing mothers, and children should check with a practitioner or pharmacist before use — do not set your own dose or duration.

Contraindications & Safety Warnings

1. Who Should Avoid Chun Pi

People with cold, weak digestion — cold hands and feet, loose stools, a cold belly.
Pregnant and nursing women — special body state; check with a practitioner first.
Children and older adults — weaker spleen-stomach function; use with care, to avoid the bitter-cold hurting the digestion.
People with liver or kidney concerns — any herb should be assessed by a professional first.
People allergic to quassia-family plants — may react to Chun Pi.

2. Drug Interactions and Food Notes

What deserves attention here is drug interaction:

Chun Pi's bitter-cold nature may affect the absorption or metabolism of blood thinners, blood-pressure, or diabetes medications. Anyone on these should check with a doctor or pharmacist before use.
There is no solid evidence of broad "food conflicts" in the way folk stories describe. The real thing to watch is herb-drug interaction — if using other medicines with Chun Pi, consult a professional first.

3. Possible Side Effects and Overuse Risks

Side effects are usually few. Taking too much or using it long-term may cause stomach discomfort, such as stomach pain or worsened diarrhea.

If you notice clear discomfort, allergic signs such as a rash, itching, or trouble breathing, ongoing vomiting, confusion, or symptoms that worsen quickly, stop use and seek medical attention promptly. Do not increase the dose on your own, to avoid discomfort from the bitter-cold nature.

Frequently Asked Questions About Chun Pi

What is Chunpi? Is it the same as Baitouweng or Huangbai?

Chunpi is the dried root bark or stem bark of Ailanthus altissima, Latin name Ailanthi Cortex. It is a common Chinese medicine centered on clearing heat and drying dampness, astringing and stopping leukorrhea, stopping diarrhea, and stopping bleeding. Baitouweng clears heat and detoxifies while cooling the blood and stopping dysentery. Huangbai clears heat and dries dampness. They cannot be used interchangeably in equal amounts. Prescribe as Chunpi. Caution in spleen-stomach deficiency cold.

What are the composition and effects of Chunpi?

Pharmacopoeial name Chunpi, Latin Ailanthus altissima (Mill.) Swingle. Bitter and astringent in taste, cold in nature, enters the Large Intestine, Stomach and Liver meridians. Functions to clear heat and dry dampness, astringe and stop leukorrhea, stop diarrhea, and stop bleeding. Used for red and white leukorrhea, damp-heat diarrhea and dysentery, chronic diarrhea and dysentery, bloody stools, and flooding and spotting. Clears heat and stops leukorrhea.

How to choose between raw and processed? Can Baitouweng replace it?

Root bark or stem bark is used raw. Baitouweng emphasizes stopping dysentery rather than strongly astringing, and cannot replace it in equal amounts. Commercial products are standardized; do not adjust arbitrarily.

What is the dosage of Chunpi? Can it be used daily as a leukorrhea-stopping tea?

Decoction, 6-9g. Modern use requires physician-determined dosage. It is not a year-round "Chunpi tea." Spleen-stomach deficiency cold will be further injured by prolonged use. Leukorrhea requires short-term, physician-determined dosage and cannot replace evaluation.

What are the contraindications of Chunpi? Can pregnant women use it?

Not suitable for spleen-stomach deficiency cold. Pregnant women require physician evaluation. Stop if loose stools or abdominal pain occur. Seek immediate medical care for severe leukorrhea or high fever.

Can Chunpi clear heat, stop leukorrhea, and stop diarrhea?

It can assist red and white leukorrhea, damp-heat diarrhea and dysentery, chronic diarrhea and dysentery, bloody stools, and flooding and spotting. It clears heat and dries dampness, astringes and stops leukorrhea, stops diarrhea, and stops bleeding, but is not a specific remedy for all leukorrhea or all diarrhea and dysentery.

Can Chunpi be taken daily as a leukorrhea-stopping or diarrhea-stopping tea?

Damp-heat leukorrhea can be used short-term in formulas; spleen-stomach deficiency cold will be further injured. The idea that "Chunpi must stop leukorrhea" cannot replace evaluation. Clearing heat and stopping leukorrhea requires physician-determined formulation and dosage.

How to choose between Chunpi, Baitouweng, Huangbai, Qianshi, and Jinyingzi?

Chunpi clears heat and astringes leukorrhea, suited to red and white leukorrhea. Baitouweng clears heat and stops dysentery. Huangbai clears heat and dries dampness. Qianshi benefits the kidney and secures essence. Jinyingzi secures essence and reduces urine. Choose Chunpi for stopping leukorrhea; Baitouweng for stopping dysentery; Huangbai for drying dampness; Qianshi for securing essence; Jinyingzi for reducing urine. Pattern differentiation applies, but large doses of Chunpi are contraindicated in spleen-stomach deficiency cold.

How is Chunpi commonly modified? What is a representative usage?

Modifications depend on the pattern. Add Qianshi for leukorrhea; add Huanglian for diarrhea and dysentery. Specify Chunpi; do not substitute Baitouweng in equal amounts for astringing.

How to select and store Chunpi?

Choose regular Chinese medicinal materials with intact root bark. Discard if moldy, damp, or abnormal in odor. Store in a dry place. Purchase "Chunpi"; do not substitute Baitouweng or Huangbai in equal amounts for clearing heat, stopping leukorrhea, and stopping diarrhea.

Related Products

Nong's Chun Pi (Tree-of-Heaven Bark) Single Herb 5:1 Concentrated Granules $50.03

Hoi Tin Chun Pi (Ailanthus Bark) Single Herb 10:1 Concentrated Granules, 100 g TCM Herbal Supplement

Hoi Tin Chun Pi (Ailanthus Bark) Single Herb 10:1 Concentrated Granules $24.77

Nong's Gu Jing Wan (Stabilize the Menses Formula) 5:1 Concentrated Granules $83.35

Medical Disclaimer — This article is provided for educational purposes only and describes traditional Chinese medicine concepts. It is not medical advice, and it is not intended to diagnose, treat, cure or prevent any disease. Always consult a qualified practitioner before using any herb, particularly if you are pregnant, nursing, taking medication or managing a diagnosed condition.