Herb Root (根 gēn)

Bai Wei

Swallowwort Root · 白薇

Cynanchum atratum Bunge · Radix Cynanchi Atrati

Also known as: Bai Long Xu (白龙须)

Bai Wei (Swallowwort Root) plant

Images shown are for educational purposes only

Bái Wēi is a cooling herb best known for treating lingering low-grade fevers, especially those caused by depleted body fluids after illness or childbirth. It clears Heat from deep within the Blood without drying out the body, which makes it unusual among cold herbs. It is also used for painful urination with blood, hot swollen sores, and sore throat.

Category Herbs that clear Deficiency Heat (清虚热药)
Therapeutic focus Fever Management Postpartum recovery Urinary Health Menopausal support

TCM Properties

Temperature

Cold

Taste

Bitter (苦 kǔ), Salty (咸 xián)

Channels entered

Stomach, Liver, Kidneys

Parts used

Root (根 gēn)

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Educational content • Consult qualified TCM practitioners for diagnosis and treatment

What This Herb Does

Every herb has a specific set of actions — here's what Bai Wei does in the body, explained in both everyday and TCM terms

Therapeutic focus

In practical terms, Bai Wei is primarily used to support these areas of health:

Fever Management Postpartum recovery Urinary Health Menopausal support

TCM Actions

In TCM terminology, these are the specific therapeutic actions that Bai Wei performs to restore balance in the body:

Clears Deficiency Heat Clears Heat and Cools the Blood Promotes Urination and Relieves Stranguria Resolves Toxicity and Heals Sores

How these actions work

'Clears deficiency Heat' (退虚热) is Bái Wēi's primary action. Unlike herbs that fight acute, high fevers from infection, Bái Wēi specializes in the low-grade, lingering fevers that arise when the body's cooling fluids (Yin) are depleted. This makes it especially useful for conditions like afternoon or evening fevers, night sweats, and the persistent low fevers that can follow childbirth or chronic illness. A classical teaching notes that Bái Wēi clears Heat from the Blood level without damaging the body's fluids, giving it a subtle nourishing quality that most cold herbs lack.

'Cools the Blood and clears Heat' (凉血清热) means Bái Wēi can address Heat that has penetrated deeply into the Blood. This applies when warm-pathogen diseases reach the nutritive (Ying) and Blood levels, showing signs like high fever, restlessness, a deep red tongue, or even delirium. Its salty taste draws it into the Blood, while its bitter and cold nature clears Heat there.

'Promotes urination and relieves painful urinary dysfunction' (利尿通淋) refers to its ability to help with 'hot' or 'bloody' urinary conditions, where there is burning, urgency, or blood in the urine. By cooling Heat in the Blood and Bladder, it helps resolve these symptoms.

'Resolves toxins and heals sores' (解毒疗疮) means Bái Wēi can be applied both internally and externally for hot, swollen sores, abscesses, sore throat, and even snakebite. Its cold nature directly counteracts the toxic Heat driving these conditions.

Patterns Addressed

In TCM, symptoms cluster into recognizable patterns of disharmony. Bai Wei is used to help correct these specific patterns.

Why Bai Wei addresses this pattern

Bái Wēi's bitter and salty Cold nature allows it to enter the Blood level through the Stomach, Liver, and Kidney channels to clear the deficiency Heat that arises when Yin is insufficient. Unlike many cold herbs that damage fluids, Bái Wēi clears Heat while subtly supporting Yin. This makes it particularly suited for Yin Deficiency Heat, where the body's cooling resources are depleted and low-grade fever persists. Classical commentators noted that it is 'cold yet does not injure Yin fluids or essence,' making it an ideal choice when the patient cannot tolerate drying or harsh cold herbs.

A practitioner would look for one or more of these signs

Low Grade Fever

Persistent low-grade fever, especially afternoon or evening

Night Sweats

Night sweats or spontaneous sweating

Tidal Fever

Bone-steaming tidal fever (骨蒸潮热)

Dry Mouth

Dry mouth and throat with a red tongue

Commonly Used For

These are conditions where Bai Wei is frequently used — but only when they arise from the specific patterns it addresses, not in all cases

Arises from: Yin Deficiency

TCM Interpretation

In TCM, persistent low-grade fevers that linger after illness, childbirth, or chronic disease are typically understood as 'deficiency Heat' (虚热). The body's Yin (its cooling, moistening, and nourishing substances) has been consumed, leaving the Yang (warming activity) relatively unchecked. This produces a smoldering, low-grade Heat rather than the intense fever of an acute infection. The Kidney and Liver Yin are most commonly involved, and the Heat often manifests in the Blood level, explaining symptoms like afternoon fevers, flushed cheeks, night sweats, and a red tongue with little coating.

Why Bai Wei Helps

Bái Wēi is especially suited to this condition because its bitter, salty, and Cold nature enters the Blood level via the Stomach, Liver, and Kidney channels to directly clear deficiency Heat. Crucially, classical commentators have emphasized that Bái Wēi clears Heat without drying out or further damaging the body's Yin fluids. This distinguishes it from many cold herbs that can worsen fluid depletion. Its subtle Yin-supporting quality makes it a go-to choice for postpartum fever, post-illness lingering fevers, and the low-grade fevers of chronic wasting conditions.

Also commonly used for

Night Sweats

Associated with Yin Deficiency

Hematuria
Pulmonary Tuberculosis

Bone-steaming tidal fever in wasting conditions

Pharyngitis

Sore throat from Heat toxin

Periappendiceal Abscess

Hot, swollen sores and boils

Postpartum Fever

Blood deficiency fever after childbirth

Abnormal Uterine Bleeding

Due to Blood Heat

Herb Properties

Every herb has an inherent temperature, taste, and affinity for specific channels — these properties determine how it interacts with the body

Temperature

Cold

Taste

Bitter (苦 kǔ), Salty (咸 xián)

Channels Entered

Stomach Liver Kidneys

Parts Used

Root (根 gēn)

Dosage & Preparation

These are general dosage guidelines for Bai Wei — always follow your practitioner's recommendation, as dosages vary based on the formula and your individual condition

Standard dosage

4.5-15g

Maximum dosage

Up to 15g in standard decoction. Do not exceed 30g due to risk of cardiac glycoside toxicity (reported toxic threshold is 30-45g), which can cause palpitations, nausea, vomiting, and dizziness.

Dosage notes

Standard decoction dose is 4.5 to 9g for most clinical applications. Higher doses up to 15g may be used for more pronounced Heat conditions such as Blood-level Heat in warm-febrile disease or persistent low-grade fever. For postpartum deficiency Heat and blood syncope, classical formulas (such as Bai Wei Tang from the Jin Gui Yao Lue) used relatively larger amounts (around 18g in the original formula, divided across multiple doses). When used for urinary tract Heat or blood in the urine, moderate doses of 6 to 9g are typical. As the herb can cause mild nausea in sensitive patients, combining with Da Zao (jujube) can help prevent gastrointestinal discomfort.

Preparation

No special decoction handling required. Bai Wei is decocted normally with other herbs. Historically, some processing methods have been described: the Lei Gong Pao Zhi Lun recommends soaking overnight in glutinous rice water before slicing and steaming; the Ben Cao Gang Mu recommends washing with wine. In modern clinical practice, the herb is typically used raw (sheng yong), simply cleaned, cut into segments, and dried.

Processing Methods

In TCM, the same herb can be prepared in different ways to change its effects — here's how processing alters what Bai Wei does

Processing method

The dried root segments are stir-fried with rice wine (黄酒) until the wine is absorbed and the herb is slightly dry.

How it changes properties

Wine processing enhances Bái Wēi's ability to enter the Blood level and improves its circulation-promoting activity. The slight warmth of wine helps guide the herb's cold nature more deeply into the channels and Blood vessels, potentially moderating its cold nature slightly.

When to use this form

Preferred when Bái Wēi is used specifically for Blood-level Heat conditions, such as Blood Heat causing menstrual irregularities or bleeding, or when a deeper penetration into the Blood level is desired.

Common Herb Pairs

These ingredients are traditionally combined with Bai Wei for enhanced therapeutic effect

Yu zhu
Yu zhu Yù Zhú 9g : Bái Wēi 3g

Bái Wēi clears deficiency Heat and gently vents pathogenic Heat outward, while Yù Zhú (玉竹) nourishes Yin and moistens dryness without trapping pathogens. Together they address the fundamental dilemma of Yin-deficient exterior syndromes: the need to release the pathogen without further depleting fluids.

When to use: When someone with an underlying Yin-deficient constitution catches a cold or flu, presenting with mild fever, dry throat, slight chills, and a red tongue.

Di Gu Pi
Di Gu Pi 1:1 (typically 6-10g each)

Both herbs clear deficiency Heat, but they complement each other: Dì Gǔ Pí (地骨皮) excels at clearing Heat from the Lung and Kidney Yin level with a gentle Yin-nourishing effect, while Bái Wēi enters the Blood level to cool Blood Heat. Together they provide broader and deeper clearance of deficiency Heat.

When to use: Yin Deficiency with bone-steaming tidal fever, night sweats, and persistent low-grade fever, especially after prolonged illness.

Dang Gui
Dang Gui Dāng Guī 6g : Bái Wēi 6g (with Rén Shēn 3g)

Dāng Guī (当归) nourishes and invigorates Blood, while Bái Wēi clears Heat from the Blood without damaging fluids. Together they address Blood Deficiency complicated by Blood Heat, as commonly seen after childbirth when depleted Blood generates deficiency Heat.

When to use: Postpartum Blood Deficiency fever, dizziness, or fainting (blood syncope), as in the classical Bái Wēi Tāng from the Quán Shēng Zhǐ Mí Fāng.

Qing Hao
Qing Hao 1:1 (typically 6-9g each)

Qīng Hāo (青蒿) is aromatic and penetrating, able to reach into the Yin level to vent lurking Heat outward. Bái Wēi cools the Blood level and clears deficiency Heat with a gentle Yin-supporting quality. Together they clear stubborn deficiency Heat from multiple levels.

When to use: Pediatric nutritional deficiency fever (疳热), or late-stage warm disease with lingering low fever, night sweats, and emaciation.

Key Formulas

These well-known formulas feature Bai Wei in a prominent role

Jia Jian Wei Rui Tang 加减葳蕤汤 Assistant

This formula from the Chong Ding Tong Su Shang Han Lun is the representative prescription for Yin-deficient exterior syndrome. Bái Wēi serves as assistant, contributing its ability to clear deficiency Heat and gently vent Blood-level Heat outward, complementing Yù Zhú's Yin-nourishing action. This formula showcases Bái Wēi's unique ability to work at the intersection of interior deficiency Heat and exterior pathogenic invasion.

Comparable Ingredients

These ingredients have overlapping uses — here's how to tell them apart

Di Gu Pi
Bai Wei vs Di Gu Pi

Both clear deficiency Heat for bone-steaming tidal fever and night sweats. Dì Gǔ Pí (地骨皮) is best suited for 'sweating bone-steaming' (有汗骨蒸) and also clears Lung Heat for cough. Bái Wēi goes deeper into the Blood level and is preferred for postpartum Blood Deficiency fever, Heat entering the nutritive/Blood level in warm diseases, and urinary conditions with blood. Bái Wēi also has detoxifying properties for sores and snakebite that Dì Gǔ Pí lacks.

Yin Chai Hu
Bai Wei vs Yin Chai Hu

Both are classified as deficiency-Heat clearing herbs. Yín Chái Hú (银柴胡) is sweet and cool, specializing in childhood nutritional deficiency fever (疳热) and is the milder of the two. Bái Wēi is bitter, salty, and colder, with stronger Blood-cooling action, making it more appropriate for Blood-level Heat, postpartum fever, and urinary bleeding. They should not be confused with Chái Hú (柴胡), which is a completely different herb that releases the exterior and soothes the Liver.

Qing Hao
Bai Wei vs Qing Hao

Both clear deficiency Heat but through different mechanisms. Qīng Hāo (青蒿) is aromatic and light, excelling at venting lurking Heat from the Yin level outward, and also treating malaria and summer-heat. Bái Wēi works more within the Blood level, has stronger Blood-cooling action, and is preferred for postpartum fever, urinary conditions, and sores. Qīng Hāo is more commonly used for malaria and summer-heat patterns.

Common Substitutes & Adulterants

Related species and common adulterations to be aware of when sourcing Bai Wei

Bai Wei is most commonly confused with Bai Qian (Cynanchum stauntonii), which belongs to the same genus and has a similar root appearance. The key distinction noted in classical texts: Bai Wei roots resemble Niu Xi (Achyranthes) but are finer and shorter, yellowish-white in color, flexible, and aromatic; Bai Qian roots are whiter-yellow, more rigid, hollow at the nodes, and break easily. Modern DNA barcoding studies have confirmed that medicinal Cynanchum species are frequently misidentified or mixed in commercial supply, posing a potential safety risk. Bai Wei may also be confused with Cynanchum bungei (Bai Shou Wu), which has different therapeutic properties entirely. Authentic Bai Wei should have the characteristic horse-tail cluster of fine roots emerging from a short, knotty rhizome.

Educational content — always consult a qualified healthcare provider or TCM practitioner before using any herb.

Toxicity Classification

Classical Chinese pharmacopoeia toxicity rating for Bai Wei

Non-toxic

Bai Wei is classified as non-toxic in the Chinese Pharmacopoeia at standard doses. However, it contains cardiac glycosides (steroidal glycosides) and a volatile oil component called 'Bai Wei Su' (baiweisin) that have digitalis-like effects on the heart, strengthening cardiac contractions and slowing the heart rate. Overdose (reported toxic threshold is approximately 30 to 45g) can produce cardiac glycoside-type poisoning symptoms including palpitations, nausea, vomiting, dizziness, headache, diarrhea, and excessive salivation. At standard dosages (4.5 to 15g), these effects are not clinically significant. Some patients may experience mild gastrointestinal discomfort such as nausea; combining the herb with Da Zao (jujube dates) can help mitigate these symptoms.

Contraindications

Situations where Bai Wei should not be used or requires extra caution

Caution

Spleen and Stomach deficiency cold with poor appetite and loose stools. Bai Wei is bitter and cold, and can further damage an already weak and cold digestive system.

Caution

Blood deficiency without Heat. As stated in the classical text Ben Cao Cong Xin: 'Suitable for Blood Heat; contraindicated in Blood deficiency.' Using this cold herb when there is no Heat to clear can further deplete already weakened Blood and Yin.

Avoid

Profuse sweating with Yang collapse (excessive perspiration with signs of Yang exhaustion). The cold nature of Bai Wei can further damage already depleted Yang Qi.

Avoid

Patients with atrioventricular block, acute endocarditis, hypokalemia, hypercalcemia, or recent acute myocardial infarction. Bai Wei contains cardiac glycosides that have digitalis-like effects and can dangerously worsen these cardiac conditions.

Caution

Diarrhea due to internal cold or deficiency. As noted in the Ben Cao Jing Shu, when diarrhea results from cold in the interior after purging, Bai Wei should not be used.

Classical Incompatibilities

Traditional Chinese pharmacological incompatibilities — herbs or substances to avoid combining with Bai Wei

Bai Wei does not appear on the classical Eighteen Incompatibilities (十八反) or Nineteen Mutual Fears (十九畏) lists. However, the Ben Cao Jing Ji Zhu (Collected Commentaries on the Classic of Materia Medica) records that Bai Wei is 'averse to' (恶, e) Huang Qi, Da Huang, Da Ji, Gan Jiang, Gan Qi (dry lacquer), Da Zao, and Shan Zhu Yu. These 'aversions' (xiang e) are a lesser category of incompatibility than the Eighteen Incompatibilities, indicating that these combinations may reduce Bai Wei's effectiveness rather than produce dangerous toxicity.

Special Populations

Important considerations for pregnancy, breastfeeding, and pediatric use

Pregnancy

Use with caution during pregnancy. Bai Wei's cold nature and Blood-cooling properties could theoretically affect fetal nourishment by depleting maternal Blood warmth. While it has been used historically in certain pregnancy-related formulas (such as Bai Wei San for pregnancy-related urinary incontinence), this was always done in carefully balanced combinations. It is not classified as a formally prohibited pregnancy herb, but its bitter-cold nature and cardiac glycoside content warrant caution. Pregnant women should not take Bai Wei without professional guidance.

Breastfeeding

Insufficient data exists on the transfer of Bai Wei's active components (particularly cardiac glycosides and steroidal saponins) into breast milk. Given the presence of digitalis-like compounds that could theoretically affect an infant's cardiovascular system, caution is warranted. Nursing mothers should avoid Bai Wei or use it only under close professional supervision at conservative dosages and for short durations.

Children

Bai Wei is used in several pediatric Chinese patent medicines including Xiao Er Gan Mao Cha (Children's Cold Tea) and Xiao Er Tui Re Kou Fu Ye (Children's Fever-Reducing Oral Liquid), indicating established pediatric use for clearing Heat and reducing fever. Dosage should be reduced to approximately one-third to one-half of the adult dose depending on the child's age and weight. It is most suitable for children presenting with Yin-deficient fever or lingering low-grade Heat after febrile illness. Due to its cold nature, it should not be used in children with weak digestion, poor appetite, or loose stools.

Drug Interactions

If you are taking pharmaceutical medications, be aware of these potential interactions with Bai Wei

Cardiac glycosides (digoxin, digitoxin): Bai Wei contains steroidal glycosides with digitalis-like activity that strengthen cardiac contraction and slow heart rate. Concurrent use with pharmaceutical cardiac glycosides could produce additive or synergistic cardiotoxic effects, potentially leading to dangerous arrhythmias. This combination should be avoided.

Antiarrhythmic medications: Due to its cardiac glycoside content, Bai Wei may interact with antiarrhythmic drugs (such as amiodarone or quinidine) by altering cardiac conduction. Use with caution and medical oversight.

Diuretics (especially potassium-depleting types): Bai Wei itself has mild diuretic properties. Hypokalemia from potassium-depleting diuretics (furosemide, hydrochlorothiazide) can increase sensitivity to cardiac glycoside toxicity. Monitor electrolytes if co-administered.

Dietary Advice

Foods and dietary considerations when taking Bai Wei

While taking Bai Wei, avoid excessively cold and raw foods if there is any underlying Spleen weakness, as the herb's cold nature can compound digestive strain. Avoid spicy, greasy, and hot-natured foods when Bai Wei is being used to clear Heat and cool Blood, as these can counteract the therapeutic intent. If using Bai Wei for Yin-deficient Heat, favor nourishing, moistening foods such as pear, lily bulb, and congee to support the Yin-nourishing strategy.

Botanical Description

Physical characteristics and morphology of the Bai Wei source plant

Cynanchum atratum (Bunge) is an upright perennial herb in the Apocynaceae (formerly Asclepiadaceae) family, growing to about 50 cm tall. The stems are densely covered with fine hairs. Leaves are arranged in opposite pairs at each node, ovate to elliptic in shape, with white downy hairs on both surfaces. The flowers are deep purple (nearly black), borne in umbel-like clusters, blooming from April to August. The fruit is a spindle-shaped follicle (a dry pod typical of the milkweed family), and the seeds are flat, pale brown, with white silky hairs for wind dispersal.

The closely related species Cynanchum versicolor (Bunge) is also used as Bai Wei. It is similar in appearance but has a twining (vine-like) upper stem and smaller flowers that open yellowish-green and gradually turn blackish-purple. Both species grow in river valleys, dry grasslands, hillside meadows, forest margins, and mountain gullies at elevations of 100 to 1,800 meters, preferring warm, moist climates. They are cold-hardy but do not tolerate waterlogging.

The medicinal part is the root and rhizome. The rhizome is short and knotty, bearing clusters of numerous slender, fibrous roots resembling a horse's tail. These roots are 10 to 25 cm long and only 1 to 2 mm in diameter, with a yellowish-brown surface and a fragrant aroma when fresh.

Sourcing & Harvesting

Where Bai Wei is sourced, when it's harvested or collected, and how to assess quality

Harvesting season

Spring and autumn. Autumn harvest is considered superior. After 2 to 3 years of cultivation, roots are dug up, washed, and dried in the sun.

Primary growing regions

The historically prized 'terroir' (dao di yao cai) source for Bai Wei is Shandong province, particularly the areas of Ju County, Yishui, and Rizhao, where the herb has been regarded as the finest quality since the late Ming dynasty and is known commercially as 'Dong Bai Wei' (Eastern Bai Wei). Other major producing regions include Liaoning and Anhui provinces. The herb is also produced in Hubei, Jiangsu, Zhejiang, Fujian, Gansu, Hebei, Shanxi, and throughout northeastern and central China. Wild populations have declined severely due to over-harvesting, making cultivated sources increasingly important.

Quality indicators

Good quality Bai Wei root is yellowish-brown on the surface, with fine, slender, straight roots that are uniform in thickness. The roots should snap cleanly when bent, producing a small puff of fine powder. The cross-section shows a yellowish-white cortex (outer layer) and a yellow woody center, with the cortex being noticeably thicker than the wood. The root should be solid (not hollow). The aroma is faint and slightly fragrant. The taste is mildly bitter. Avoid roots that are dark, hollow, overly soft, or have an off smell. The best commercial grade is known as 'Dong Bai Wei' (from Shandong), with roots that are fine, straight, and pale yellowish externally with a whitish interior.

Classical Texts

Key passages from the classical Chinese medical texts that describe Bai Wei and its therapeutic uses

Shen Nong Ben Cao Jing (The Divine Farmer's Classic of Materia Medica)

Chinese: 主暴中风，身热肢满，忽忽不知人，狂惑邪气，寒热酸疼，温疟洗洗，发作有时。

English: Treats sudden wind-strike with bodily Heat and limb fullness, sudden unconsciousness, manic confusion from pathogenic Qi, alternating chills and fever with aching pain, and warm-type malaria with periodic attacks.

Ming Yi Bie Lu (Supplementary Records of Famous Physicians)

Chinese: 疗伤中淋露。下水气，利阴气，益精，久服利人。

English: Treats internal injury with vaginal discharge and spotting. Resolves water-Qi, benefits Yin-Qi, supplements essence. Long-term use benefits a person.

Ben Cao Cong Xin (New Compilation of Materia Medica)

Chinese: 血热相宜，血虚则忌。

English: Suitable for Blood Heat; contraindicated in Blood deficiency.

Ben Cao Jing Shu (Commentary on the Classic of Materia Medica)

Chinese: 白薇，《本经》所主诸证，皆由热淫于内之所发。

English: All the conditions that Bai Wei treats according to the Shen Nong Ben Cao Jing arise from Heat raging internally.

Historical Context

The history and evolution of Bai Wei's use in Chinese medicine over the centuries

Bai Wei has a documented medicinal history spanning over 2,000 years. It was first recorded in the Shen Nong Ben Cao Jing (Divine Farmer's Classic of Materia Medica), where it was classified as a middle-grade herb. Its aliases evolved through the centuries: in the earliest texts it appeared as Wei Cao (薇草), Zhi Wei Lao (知微老), and Lao Gua Piao Gen (老瓜瓢根), then during the Six Dynasties period as Bai Mu (白幕), Gu Mei (骨美), and Chun Cao (春草, 'spring grass'). The name 'Bai Wei' (白薇, literally 'white subtlety') was consolidated in the Ben Cao Gang Mu (Comperta of Materia Medica) during the Ming dynasty.

Zhang Zhongjing, the great Han dynasty physician, used Bai Wei in his clinical formulas. In the Jin Gui Yao Lue (Essentials from the Golden Cabinet), Bai Wei appears in formulas for postpartum deficiency Heat, nausea, and blood syncope (Bai Wei Tang). The herb also features in the Tong Su Shang Han Lun's (Popular Guide to Cold Damage) famous Jia Jian Wei Rui Tang (Modified Solomon's Seal Decoction) for Yin-deficient exterior patterns, where it works alongside Yu Zhu (Solomon's Seal), Bo He (mint), and Dan Dou Chi to clear Heat, nourish Yin, and gently release the exterior. The Ben Cao Jing Shu provides an important clinical discussion of Bai Wei's role in gynecological formulas for infertility, explaining that it clears the Blood-level Heat and nourishes Yin that underlies many cases of Blood deficiency and inability to conceive.

Modern Research

4 published studies investigating the pharmacological effects or clinical outcomes of Bai Wei

1

Comprehensive ethnopharmacology, phytochemistry, and pharmacology review of Cynanchum atratum (2021)

Gu H, Li Y, et al. Journal of Ethnopharmacology, 2022, 284, 114788.

A thorough review covering the traditional uses, chemical constituents (over 100 compounds including C21 steroidal saponins, acetophenones, alkaloids, and volatile oils), and pharmacological activities of Bai Wei. The review documents evidence for anti-inflammatory, antipyretic, diuretic, anti-tumor, antiviral (including anti-TMV), immunomodulatory, and antibacterial (against pneumococcus) effects. The authors note that safety evaluation and quality standardization still require further study.

PubMed
2

Immunosuppressive C21 steroidal glycosides from Cynanchum atratum root (2015)

Zhang ZJ, Ding ML, Tao LJ, Zhang M, Xu XH, Zhang CF. Fitoterapia, 2015, 105, 194-201.

Six new C21 steroidal glycosides (atratcynosides A through F) were isolated from Bai Wei root. Three of these compounds showed significant immunosuppressive activity, inhibiting T-lymphocyte proliferation in a dose-dependent manner with IC50 values of 3.3 to 7.0 micromolar. Structure-activity relationships were also analyzed.

PubMed
3

Cynanchum atratum inhibits atopic dermatitis development in DNCB-induced mice (2017)

Choi YY, Kim MH, Lee H, Ahn KS, Um JY, Lee SG, Kim J, Yang WM. Biomedicine & Pharmacotherapy, 2017, 90, 321-327.

Topical application of an aqueous extract of Bai Wei root reduced atopic dermatitis symptoms in a mouse model, including lowered serum IgE levels, reduced scratching behavior, decreased skin thickening, and reduced mast cell infiltration and pro-inflammatory cytokine expression. The study supports the traditional use of Bai Wei for inflammatory skin conditions.

Link
4

Bioactive constituents of the roots of Cynanchum atratum (2001)

Bai H, Li W, Koike K. Journal of Natural Products, 2001, 64(9), 1241-1244.

Isolated a novel biphenylneolignan and two new glycosides (atratoglaucosides A and B) from the roots. One known compound, a glaucogenin C glycoside, showed significant cytotoxic effects and inhibited TNF-alpha formation in macrophage cell lines, providing a pharmacological basis for the herb's traditional anti-inflammatory use.

Link

Research on individual TCM herbs is growing but still limited by Western clinical trial standards. These studies provide emerging evidence and should be considered alongside practitioner expertise.