Herb Whole plant / Aerial parts (全草 quán cǎo)

Da Ji

Japanese thistle · 大蓟

Cirsium japonicum Fisch. ex DC. · Herba seu Radix Cirsii Japonici

Also known as: Japanese thistle, Plum thistle, Large thistle,

Da Ji (Japanese thistle) plant

Images shown are for educational purposes only

Japanese thistle is a cooling herb primarily used to stop bleeding caused by excess internal heat, such as nosebleeds, coughing blood, or heavy uterine bleeding. It also helps reduce swelling from abscesses and boils, and can be applied directly to wounds. It is one of the key herbs in the classical emergency bleeding formula Shí Huī Sǎn (Ten Charred Substances Powder).

Category Hemostatic herbs (止血药) Herbs that cool the Blood and stop bleeding (凉血止血药)
Therapeutic focus Bleeding Disorders Women's Health Skin Health Liver Health

TCM Properties

Temperature

Cool

Taste

Sweet (甘 gān), Bitter (苦 kǔ)

Channels entered

Heart, Liver

Parts used

Whole plant / Aerial parts (全草 quán cǎo)

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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 Da Ji does in the body, explained in both everyday and TCM terms

Therapeutic focus

In practical terms, Da Ji is primarily used to support these areas of health:

Bleeding Disorders Women's Health Skin Health Liver Health

TCM Actions

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

Cools the Blood and Stops Bleeding Invigorates Blood and Reduces Swelling Clears Heat and Resolves Toxicity

How these actions work

'Cools the Blood and stops bleeding' means Dà Jì enters the Blood level and clears Heat that is forcing blood out of the vessels. When internal Heat becomes intense, it can cause blood to move recklessly, leading to various types of bleeding such as nosebleeds, coughing or vomiting blood, blood in the urine or stool, and heavy menstrual or uterine bleeding. The blood in these cases is typically bright red in color because of the underlying Heat. Dà Jì's cool nature and sweet-bitter taste allow it to calm this Heat in the Blood, helping the blood return to its normal pathways. The fresh juice of the herb is considered the most effective form for this action. When the herb is charred (炒炭), its cooling nature is reduced but its ability to physically stop bleeding through astringency is enhanced.

'Disperses Blood stasis and reduces swelling' means Dà Jì does not simply stop bleeding by constricting. It also has the ability to move stagnant blood and reduce swollen, inflamed tissue. This makes it especially useful for abscesses and boils, whether internal (such as intestinal or lung abscesses) or external (skin sores and carbuncles). Classical sources note that this ability to treat swellings and abscesses is a key distinction between Dà Jì and its close relative Xiǎo Jì (small thistle), which is weaker in this regard.

'Clears Heat and resolves toxins' refers to the herb's broader ability to address hot, toxic conditions such as infected sores, boils, and inflammatory swellings. It can be used both internally as a decoction and externally as a fresh poultice. Modern clinical use extends this to conditions like mastitis and hepatitis where Heat toxins play a role.

Patterns Addressed

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

Why Da Ji addresses this pattern

Dà Jì is cool in temperature, sweet and bitter in taste, and enters the Heart and Liver channels. These properties make it directly suited to addressing Blood Heat, a condition where excessive Heat in the Blood forces it out of the vessels. The Liver stores the Blood and the Heart governs it, so Dà Jì's channel affinity allows it to cool the Blood at its source. Its bitter taste helps descend and drain Heat, while its sweet taste moderates harshness and supports the Blood. Unlike purely cold or bitter herbs that might congeal the Blood, Dà Jì also gently moves stasis, stopping bleeding without trapping old blood in place.

A practitioner would look for one or more of these signs

Nosebleeds

Bright red blood, often from Heat rising upward

Hematemesis

Vomiting blood due to Heat forcing blood upward

Hemoptysis

Coughing blood, bright red in color

Hematuria

Blood in the urine from Heat in the lower burner

Bleeding

Heavy or irregular uterine bleeding with bright red blood

Commonly Used For

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

Arises from: Blood Heat

TCM Interpretation

In TCM, abnormal uterine bleeding (called bēng lòu, 崩漏) is often understood as a failure of the body to keep blood contained within the vessels. When Heat enters the Blood level and affects the Liver (which stores the Blood) and the Chong and Ren channels (which regulate menstruation), it can cause blood to move recklessly, leading to heavy, prolonged, or irregular bleeding. The blood is typically bright red in color, and the person may also feel restless, thirsty, or feverish. The tongue is often red with a rapid pulse.

Why Da Ji Helps

Dà Jì enters the Heart and Liver channels, giving it direct access to the organs that govern and store the Blood. Its cool temperature and bitter-sweet taste allow it to clear the Heat that is disrupting normal blood flow, while its ability to disperse stasis prevents old blood from being trapped after the acute bleeding stops. Classical physicians frequently used fresh Dà Jì juice for urgent uterine bleeding, and it appears in formulas like Shí Huī Sǎn for this purpose. Its action is stronger than Xiǎo Jì for this type of bleeding.

Also commonly used for

Nosebleeds

Due to Blood Heat forcing blood upward

Hemoptysis

Coughing blood from lung heat or bronchiectasis

Hematemesis

Vomiting blood from upper GI bleeding

Hematuria

Blood in the urine due to heat in the lower burner

Periappendiceal Abscess

Intestinal or lung abscesses with heat and toxins

Boils

Hot, toxic skin lesions; fresh herb applied topically

Mastitis

Breast abscess with inflammation

Hepatitis

Especially acute infectious hepatitis with liver heat

Trauma

External application of powdered root to stop bleeding

Herb Properties

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

Temperature

Cool

Taste

Sweet (甘 gān), Bitter (苦 kǔ)

Channels Entered

Heart Liver

Parts Used

Whole plant / Aerial parts (全草 quán cǎo)

Dosage & Preparation

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

Standard dosage

1.5–3g (vinegar-processed, in decoction)

Maximum dosage

Do not exceed 3g internally (vinegar-processed). Raw herb should NOT be taken internally. The reported toxic dose of raw Da Ji is 9–15g. Even at standard doses, patients may experience nausea, vomiting, and diarrhea.

Dosage notes

The standard decoction dose is 1.5–3g of vinegar-processed (醋制) Da Ji. For powdered form taken in capsules, the dose is typically 0.3–1g per administration, taken every other day or every 2–3 days, as used in clinical reports for ascites treatment. When used in pill or powder form (as in classical formulas like Shi Zao Tang), even smaller amounts are appropriate. The herb should be taken on an empty stomach for fluid-purging indications, and treatment courses should be limited (typically 6–9 doses). Dosing with dates (大枣) is a traditional strategy to buffer the Spleen from damage. During treatment, a low-salt diet is recommended, and 'cold, raw, spicy foods, fish, and other irritating foods' should be avoided.

Preparation

Raw Da Ji (生大戟) should only be used externally (crushed and applied as a poultice for snakebites, abscesses, and toxic swellings). For all internal use, vinegar-processed Da Ji (醋京大戟) is required: the herb slices are soaked in rice vinegar and then slowly cooked until the vinegar is fully absorbed (30 kg vinegar per 100 kg herb). This processing significantly reduces toxicity and moderates the violent purging action. In classical practice, cooking with dates (枣煮) was another method to protect the Spleen.

Processing Methods

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

Processing method

The cut herb segments or root slices are stir-fried in a wok over high heat (武火) until the surface turns blackish-brown. A small amount of clean water is sprinkled on to extinguish any sparks, and the material is then removed and cooled thoroughly. The key requirement is to 'preserve the nature' (存性), meaning the herb should be charred on the outside but not fully incinerated.

How it changes properties

Charring significantly reduces the herb's cooling nature, making it less likely to damage the Spleen and Stomach with excessive cold. The astringent, hemostatic action is markedly enhanced through the charring process. The raw herb is stronger at cooling Blood and resolving abscesses, while the charred form prioritizes physical stopping of bleeding through increased astringency.

When to use this form

Use the charred form (Dà Jì Tàn) when the primary goal is to stop active, urgent bleeding such as vomiting blood, coughing blood, or heavy uterine hemorrhage. It is the form used in Shí Huī Sǎn. The raw form is preferred when the clinical picture includes abscesses, toxic swellings, or when cooling Blood Heat is the priority over pure hemostasis.

Common Herb Pairs

These ingredients are traditionally combined with Da Ji for enhanced therapeutic effect

Xiao Ji
Xiao Ji 1:1 (equal parts)

Dà Jì and Xiǎo Jì are the classical thistle pair (二蓟). Together they strongly cool the Blood and stop bleeding with a broader scope than either alone. Dà Jì contributes stronger stasis-dispersing and abscess-resolving power, while Xiǎo Jì adds mild diuretic action that helps clear Heat through urination. The combination addresses bleeding from virtually any location in the body.

When to use: Blood Heat causing bleeding from multiple sites or severe hemorrhage. This pair forms the King herb duo in Shí Huī Sǎn (Ten Charred Substances Powder) for emergency upper body bleeding.

Qian Cao
Qian Cao 1:1

Dà Jì cools the Blood and stops bleeding while Qián Cǎo (madder root) invigorates Blood circulation and also stops bleeding. Together they stop hemorrhage without trapping stasis, combining a cooling approach with active blood-moving support. This pair is particularly effective for coughing or vomiting blood.

When to use: Hemoptysis or hematemesis due to Blood Heat with concurrent blood stasis. Especially useful when the bleeding is accompanied by signs of stagnation such as dark clots.

Di Yu
Di Yu 1:1

Dà Jì cools Blood and disperses stasis from the upper and middle body, while Dì Yǔ (sanguisorba root) is astringent and particularly effective for lower body bleeding and intestinal conditions. Together they provide comprehensive hemostatic coverage and are especially effective for intestinal abscesses with bleeding.

When to use: Intestinal bleeding, intestinal abscess, or bloody dysentery with Heat toxins. Also used for lower body bleeding such as hemorrhoidal bleeding.

Xia Ku Cao
Xia Ku Cao 1:1

Dà Jì cools Blood Heat through the Liver channel while Xià Kū Cǎo (self-heal) clears Liver Fire and softens hardness. Together they address Liver Heat from two angles, making this pair effective for hypertension related to Liver Fire rising, as well as for scrofula and nodular swellings.

When to use: Hypertension with headache, dizziness, and red eyes due to Liver Heat. Also for nodular swellings or scrofula with Heat signs.

Key Formulas

These well-known formulas feature Da Ji in a prominent role

Shi Hui San 十灰散 King

Shí Huī Sǎn (Ten Charred Substances Powder) from the Shí Yào Shén Shū is the most iconic formula featuring Dà Jì. It serves as King herb alongside Xiǎo Jì, showcasing its core action of cooling Blood and stopping bleeding. All ten herbs are charred to enhance hemostatic action, and the formula is used as an emergency treatment for acute upper body bleeding (vomiting blood, coughing blood, nosebleed) with bright red blood due to Blood Heat.

Comparable Ingredients

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

Xiao Ji
Da Ji vs Xiao Ji

Both are thistles that cool Blood and stop bleeding, but they differ in important ways. Dà Jì is stronger at dispersing stasis and resolving abscesses and swellings, making it better suited for bleeding with concurrent abscess formation or toxic swellings. Xiǎo Jì is milder but uniquely capable of promoting urination and clearing Heat through the urinary tract, making it the preferred choice for blood in the urine (hematuria) and painful urinary conditions. Classical texts note that Dà Jì 'treats both bleeding and abscesses' while Xiǎo Jì 'focuses on blood alone and cannot reduce swelling.'

Ce Bai Ye
Da Ji vs Ce Bai Ye

Both cool Blood and stop bleeding, but Cè Bǎi Yè (biota leaf) also has an astringent quality and is especially effective for coughing blood and bleeding from the Lungs. It also enters the Lung channel, while Dà Jì primarily works through the Heart and Liver. Dà Jì is preferred when there is concurrent stasis or abscesses, while Cè Bǎi Yè is better for straightforward Blood Heat bleeding in the upper body, particularly with dry cough.

Bai Mao Gen
Da Ji vs Bai Mao Gen

Both cool Blood and stop bleeding, but Bái Máo Gēn (imperata root) is sweet and cold with strong diuretic properties, making it especially effective for hematuria and promoting urination. It also generates fluids, so it is better for patients who are thirsty or show signs of Yin damage from Heat. Dà Jì is stronger at dispersing Blood stasis and treating abscesses, making it the better choice when swelling or stagnation accompanies the bleeding.

Common Substitutes & Adulterants

Related species and common adulterations to be aware of when sourcing Da Ji

The most significant confusion in the Da Ji market is between two entirely different species: 1. Jing Da Ji (京大戟) — Euphorbia pekinensis Rupr. (Euphorbiaceae): This is the authentic herb recorded in classical texts. It has stronger water-purging and fluid-draining action but is more toxic. 2. Hong Da Ji (红大戟) — Knoxia valerianoides (Rubiaceae): This is a different plant from a different botanical family. It has lower toxicity and is better at dispersing swellings and dissipating nodules, but is weaker at draining fluids. Despite being the more commonly traded variety in modern markets, it was NOT the Da Ji described in historical materia medica texts. Since the 1995 edition, the Chinese Pharmacopoeia has listed these as separate entries. Classical formulas calling for Da Ji (such as Shi Zao Tang) should use Jing Da Ji. Additionally, Li Shizhen warned about 'Northern Mian Da Ji' (绵大戟), a white-rooted variety with soft, cotton-like bark that is extremely harsh and can cause vomiting of blood in weak patients. This may correspond to Stellera chamaejasme (狼毒), which should never be substituted.

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

Toxicity Classification

Classical Chinese pharmacopoeia toxicity rating for Da Ji

Toxic

The toxic components of Da Ji include euphorbia glycosides (大戟苷), anthraquinone derivatives, and casbane-type diterpenoids such as pekinenin C. The milky latex found throughout the plant is highly irritating: skin contact can cause dermatitis, inflammation, and photosensitivity, while ingestion of the raw root causes severe inflammation and ulceration of the oral mucosa, throat, and gastrointestinal tract. The internal toxic dose is reported at 9–15g of raw herb. Symptoms of poisoning progress from throat swelling and congestion, violent vomiting (possibly with blood), watery diarrhea, and abdominal pain, to headache, dizziness, palpitations, and blood pressure drop. Severe cases can progress to dehydration, acid-base imbalance, tremors, convulsions, coma, respiratory paralysis, and death. Processing with vinegar (醋制) significantly reduces toxicity. Modern toxicology studies confirm that the LD50 is significantly higher (i.e., less toxic) after vinegar processing compared to the raw herb. Cooking with dates (枣) was another traditional method to protect the Spleen from damage. The raw herb should only be used externally; all internal use requires vinegar-processed Da Ji (醋京大戟). Classical sources note that Shi Chang Pu (Acorus calamus rhizome) can help resolve Da Ji toxicity.

Contraindications

Situations where Da Ji should not be used or requires extra caution

Avoid

Pregnancy: Da Ji has documented uterine-stimulating effects and is traditionally noted to 'promote menstruation and cause miscarriage' (通经堕胎). It is strictly prohibited during pregnancy.

Avoid

Concurrent use with Gan Cao (Glycyrrhiza, licorice): This is a classical Eighteen Incompatibilities (十八反) pair. Modern research has confirmed that combining Da Ji with licorice increases toxicity, potentially through enhanced nephrotoxicity via mitochondria-dependent apoptosis.

Avoid

Heart failure or severe cardiovascular disease: The herb's powerful fluid-purging action can cause dangerous dehydration and electrolyte imbalance, worsening cardiac function.

Avoid

Esophageal varices: The violent purging action risks triggering hemorrhage in patients with portal hypertension and esophageal varices.

Avoid

Deficiency-cold (Xu Han) patterns with edema: Classical texts warn that using Da Ji in patients with Spleen-Kidney Yang deficiency and Yin-type edema can be lethal. The Ben Jing Feng Yuan states: 'In Spleen, Stomach, Liver, and Kidney deficiency-cold with Yin water flooding, using this herb brings instant death.'

Caution

Physical debility or constitutional weakness: Da Ji is extremely harsh and can severely deplete Qi and damage Yin in already weakened patients. Only appropriate for excess (Shi) patterns in patients with adequate constitution.

Caution

Elderly patients or those with chronic illness: Requires careful dosage adjustment and close monitoring due to the risk of severe fluid and electrolyte loss.

Classical Incompatibilities

Traditional Chinese pharmacological incompatibilities — herbs or substances to avoid combining with Da Ji

Da Ji is incompatible with Gan Cao (甘草, Glycyrrhiza/Licorice) according to the Eighteen Incompatibilities (十八反). This is one of the most well-known classical contraindicated pairings. The Ben Cao Jing Ji Zhu states: '反甘草' (opposes Gan Cao). Modern animal studies have confirmed this: combining Da Ji with Gan Cao increases toxicity, with the LD50 decreasing significantly compared to Da Ji used alone. A 2020 study demonstrated that their combined use enhances nephrotoxicity through increased ROS-mediated mitochondrial apoptosis.

Special Populations

Important considerations for pregnancy, breastfeeding, and pediatric use

Pregnancy

Absolutely contraindicated during pregnancy. Classical texts explicitly state that Da Ji 'promotes menstruation and causes miscarriage' (通经堕胎). Pharmacological research on a related Japanese variety of Euphorbia pekinensis demonstrated uterine-stimulating effects in both isolated and in-situ uterus preparations in rabbits and guinea pigs. The violent purging action also poses a serious risk of triggering premature labor through severe gastrointestinal spasm and dehydration. There is no safe dose during pregnancy.

Breastfeeding

Not recommended during breastfeeding. Da Ji is classified as toxic and contains irritating diterpenoids and latex compounds that may transfer into breast milk. The violent purgative action also risks causing dehydration and electrolyte disturbance in the mother, potentially impairing milk production and quality. No safety data exists for breastfeeding use. If the herb is deemed clinically essential, breastfeeding should be suspended during treatment.

Children

Da Ji is generally not suitable for children due to its strong toxicity and violent purging action. If used in older children for serious conditions under strict practitioner supervision, dosage must be significantly reduced (often less than half the adult dose). It is absolutely contraindicated in infants and young children. Any pediatric use requires very close monitoring for dehydration, electrolyte imbalance, and gastrointestinal distress.

Drug Interactions

If you are taking pharmaceutical medications, be aware of these potential interactions with Da Ji

Diuretics: Da Ji has potent fluid-purging effects. Concurrent use with pharmaceutical diuretics (furosemide, hydrochlorothiazide, spironolactone) may cause dangerous additive fluid loss, dehydration, and electrolyte imbalance (especially hypokalemia and hyponatremia).

Cardiac glycosides (digoxin): The severe diarrhea and electrolyte depletion (particularly potassium loss) caused by Da Ji can increase the risk of digoxin toxicity and cardiac arrhythmias.

Antihypertensives: Da Ji extracts have demonstrated peripheral vasodilatory effects and can inhibit the pressor action of epinephrine. Combined use with antihypertensive medications may cause excessive blood pressure reduction.

Anticoagulants/Antiplatelets: Da Ji has traditional indications for moving Blood and has been associated with bloody stool and bloody vomit at toxic doses. Caution is warranted when combining with warfarin, heparin, or antiplatelet agents due to potential increased bleeding risk.

Dietary Advice

Foods and dietary considerations when taking Da Ji

During treatment with Da Ji, follow a strict low-salt diet to maximize the fluid-draining therapeutic effect. Avoid cold, raw, and spicy foods. Avoid fish, pork head meat, and other traditionally recognized 'stirring foods' (发物) that may aggravate side effects. Do not consume licorice (甘草) in any form, including herbal teas or confections, due to the classical incompatibility. If nausea or vomiting occurs after taking the herb, consuming fruit or cool sugar water can help ease the reaction.

Botanical Description

Physical characteristics and morphology of the Da Ji source plant

Euphorbia pekinensis Rupr. is a perennial herbaceous plant of the Euphorbiaceae (spurge) family, growing 30–90 cm tall. The entire plant exudes a white, milky latex when cut or broken. The root is stout and conical with lateral branches. The stem branches from the upper portions and is covered with fine white hairs.

The leaves are alternate, nearly sessile, narrowly oblong-lanceolate, 3–8 cm long and 6–12 mm wide, with blunt or pointed tips and entire margins. The upper leaf surface is smooth while the lower surface has hairs along the midrib. In spring, the plant produces red-tipped new shoots. It flowers from March to May with small yellowish-purple cyathia (cup-shaped flower clusters typical of Euphorbia). The fruit is a three-ridged, globular capsule. The plant grows commonly along roadsides, hillsides, wastelands, and in shaded or moist woodland margins.

Sourcing & Harvesting

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

Harvesting season

Autumn (after the above-ground parts wither) through early spring (before new shoots emerge), typically October through March.

Primary growing regions

Jiangsu, Sichuan, Jiangxi, and Guangxi provinces are the main producing regions. Historically, Li Shizhen noted in the Ben Cao Gang Mu that Hangzhou's purple Da Ji (杭州紫大戟) was considered the finest quality, followed by Jiangnan varieties. The herb is widely distributed across most of China (except Xinjiang, Guangdong, Hainan, and Tibet), as well as in parts of North Korea and Japan. It commonly grows wild in northeastern China, eastern China, and Hebei province.

Quality indicators

Good quality Jing Da Ji (京大戟) root is irregularly conical, slightly curved, often branched, 10–20 cm long and 1.5–4 cm in diameter. The surface should be greyish-brown to dark brown, rough, with longitudinal wrinkles, transverse lenticels, and lateral root scars. The top end is slightly swollen with multiple stem base and bud scars. The texture should be hard and difficult to break, with a cross-section that is off-white to pale yellow and distinctly fibrous. The smell is faint and the taste is slightly bitter and astringent. Roots that are uniform, plump, tender-textured without excessive rootlets are considered best. Note: Hong Da Ji (红大戟, Knoxia valerianoides) from the Rubiaceae family looks different: it is spindle-shaped, 6–14 cm long, reddish-brown, with a brittle texture and red-brown cross-section, and a spicy taste that irritates the throat.

Classical Texts

Key passages from the classical Chinese medical texts that describe Da Ji and its therapeutic uses

Shen Nong Ben Cao Jing (《神农本草经》)

Original: 大戟，味苦寒。主蛊毒十二水，腹满急痛，积聚，中风，皮肤疼痛，吐逆。

Translation: Da Ji, bitter in taste, cold in nature. Governs gu-toxin and the twelve types of water disease, abdominal fullness and acute pain, accumulations and gatherings, wind-strike, skin pain, and vomiting.

Ben Cao Gang Mu (《本草纲目》, Li Shizhen)

Original: 其根辛苦，戟人咽喉，故名。今俚人呼为下马仙，言利人甚速也。

Translation: Its root is acrid and bitter, pricking the throat like a halberd (ji), hence the name. Common folk call it 'Xia Ma Xian' (Dismount-the-Horse Immortal), meaning it purges people extremely swiftly.

Ben Cao Gang Mu (Li Shizhen, on the Control of Phlegm)

Original: 大戟能泄脏腑之水湿，甘遂能行经隧之水湿，白芥子能散皮里膜外之痰气，惟善用者，能收奇功也。

Translation: Da Ji can drain water-dampness from the organs, Gan Sui can move water-dampness through the channels, and Bai Jie Zi can disperse phlegm between the skin and membranes. Only a skilled practitioner can achieve remarkable results with these.

Ben Jing Feng Yuan (《本经逢原》)

Original: 脾胃肝肾虚寒，阴水泛滥，犯之立毙，不可不审。

Translation: When the Spleen, Stomach, Liver, and Kidney are in deficiency-cold and Yin water floods, taking this herb brings instant death. One must examine the situation with utmost care.

Historical Context

The history and evolution of Da Ji's use in Chinese medicine over the centuries

Da Ji was first recorded in the Shen Nong Ben Cao Jing (Divine Farmer's Classic of Materia Medica), where it was classified as a lower-grade (下品) herb, indicating potent but potentially dangerous medicinal action. The name '大戟' literally means 'great halberd,' because, as Li Shizhen explained, its root is so acrid and bitter that it 'pricks the throat like a halberd.' Its folk name Xia Ma Xian (下马仙, 'Dismount-the-Horse Immortal') vividly conveys its dramatic and rapid purging effect.

Throughout Chinese medical history, Da Ji was a key component of the famous Shi Zao Tang (Ten Jujubes Decoction) from Zhang Zhongjing's Jin Gui Yao Lue, where it is combined with Gan Sui and Yuan Hua to treat fluid accumulation in the chest and flanks. Li Shizhen's discussion of the Kong Xian Dan (Control Phlegm Pill) from Chen Wuze's San Yin Ji Yi Bing Zheng Fang Lun is a celebrated passage explaining how Da Ji drains water-dampness from the organs. The pediatrician Qian Yi (Song Dynasty) used Da Ji as the sole ingredient in the Bai Xiang Wan (Hundred Auspicious Pill) for treating dark, sunken smallpox lesions. An important historical development is the confusion between Jing Da Ji (京大戟, Euphorbiaceae) and Hong Da Ji (红大戟, Rubiaceae). Classical texts consistently refer to Euphorbia pekinensis, but in modern practice Hong Da Ji (Knoxia valerianoides) became more widely traded due to its lower toxicity, despite having different chemical composition and therapeutic strengths.

Modern Research

4 published studies investigating the pharmacological effects or clinical outcomes of Da Ji

1

Comprehensive review of botany, traditional uses, phytochemistry, pharmacology, quality control, and toxicology of Euphorbia pekinensis roots (2024)

Liang Q, Hu JX, Liang ZS, Xiao LL, Xu WH. Natural Product Research, 2025, 39(10), 2912-2928.

A systematic review cataloguing 79 structurally diverse compounds isolated from Da Ji roots, principally diterpenoids, triterpenoids, tannins, and phenols. The review confirmed that diterpenoids are the primary bioactive constituents and that extracts demonstrate diuretic, purgative, anti-inflammatory, and cytotoxic effects, supporting the traditional medicinal uses of the herb.

2

In vitro nephrotoxicity induced by herb-herb interaction between Radix Glycyrrhizae and Radix Euphorbiae Pekinensis (2020)

Chen M et al. Evidence-Based Complementary and Alternative Medicine, 2020, Article ID 8745765.

This study investigated the classical incompatibility between Da Ji and licorice (Gan Cao). It found that their combined use increased nephrotoxicity through enhanced production of reactive oxygen species (ROS), leading to mitochondria-dependent apoptosis. The major toxic compounds responsible were identified as DEAX and DEA, providing a modern scientific basis for the ancient Eighteen Incompatibilities theory.

PubMed
3

Toxicity of Pekinenin C from Euphorbia Pekinensis Radix on rat small intestinal crypt epithelial cell and its apoptotic mechanism (2016)

Dai CC, Jiang JH, Tang YP, Duan JA et al. International Journal of Molecular Sciences, 2016, 17(6), 924.

This preclinical study isolated the casbane diterpenoid pekinenin C from Da Ji roots and demonstrated its severe cytotoxicity against intestinal epithelial cells (IEC-6). The toxic mechanism involved cell cycle arrest and induction of apoptosis, helping to explain the gastrointestinal toxicity observed with this herb.

PubMed
4

Euphorbia pekinensis glycosphingolipids disrupt gut motility and fluid balance via TRPA1 activation in enterochromaffin cells (2026)

Cao J, Liu BB et al. British Journal of Pharmacology, 2026.

A recent pharmacological study identified toxic glycosphingolipids (GSLs) from Da Ji that activate TRPA1 receptors on intestinal enterochromaffin cells, triggering excessive serotonin (5-HT) release. This serotonin surge causes aberrant intestinal smooth muscle contraction and epithelial hypersecretion, explaining the severe diarrhea and abdominal pain characteristic of Da Ji toxicity.

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.