Si Ji Qing

Si Ji Qing (Folium Ilicis Chinensis) is the dried leaf of Ilex chinensis Sims, an evergreen shrub or small tree of the family Aquifoliaceae (holly family). In the traditional TCM classification system, Si Ji Qing is considered bitter, astringent, and cold in nature. It enters the Heart, Lung, and Stomach meridians, giving it a role in formulas that address toxic Heat, Blood Heat with bleeding, and inflammatory conditions of the skin and tissues, particularly burns and wounds.

Botanical description: Ilex chinensis is an evergreen shrub or small tree growing 3–10 meters tall. The bark is grayish-brown and smooth. The leaves are alternate, petiolate, leathery, elliptic to lanceolate-elliptic, 4–10 cm long and 1.5–3.5 cm wide, with a dark glossy green upper surface and a paler lower surface. The leaf margin is typically serrate with spiny teeth, although mature leaves may have smoother margins. The leaf apex is acute to acuminate, and the base is cuneate. The plant is dioecious, with small white or pale greenish flowers arranged in axillary cymes. The fruit is a globose, red drupe 6–8 mm in diameter, containing 4–5 pyrenes. The plant flowers from April to June and fruits from August to November. The leaves are harvested year-round, with summer and autumn harvests considered optimal for active constituent content, and are dried in the shade.

Habitat and cultivation: I. chinensis is native to central and southern China, including the provinces of Zhejiang, Jiangsu, Anhui, Jiangxi, Hunan, Hubei, Fujian, Guangdong, and Guangxi. It grows wild in mixed forests, along forest margins, and on hillsides, and is also cultivated as an ornamental and medicinal plant. The plant prefers warm, humid climates and well-drained, slightly acidic soils. It is shade-tolerant and grows well under partial canopy. The medicinal material is primarily wild-harvested, with some cultivation in the traditional producing regions. Because the plant is evergreen and the leaves can be harvested year-round, the medicinal material is available throughout the year — a characteristic reflected in the Chinese name Si Ji Qing, which translates as "green in all four seasons." After harvest, the leaves are cleaned and dried in a well-ventilated, shaded area to preserve their green color and active constituents.

Quality markers: High-quality Si Ji Qing consists of intact, dark green, glossy leaves with a leathery texture, free of yellowing, mold, and excessive stem material. Pharmacopoeial and regional standards emphasize the content of total triterpenoids (expressed as ursolic acid equivalents), tannins, and flavonoids. Premium-grade material is characterized by its deep green color, intact leaf blades with prominent venation, a faint characteristic odor, and a bitter, astringent taste. Material should be stored in a dry, well-ventilated place protected from light to preserve the triterpenoid and tannin content.

In the traditional Chinese medicine theoretical framework, Si Ji Qing is understood in terms of its effects on specific patterns of disharmony (zheng). Because Si Ji Qing enters the Heart, Lung, and Stomach meridians and has a bitter, astringent, cold quality, it is traditionally indicated for a range of patterns involving toxic Heat, Blood Heat with bleeding, and inflammatory conditions of the skin and tissues.

Clearing Heat and resolving toxicity: Si Ji Qing is considered an effective herb in TCM for clearing Heat and resolving toxicity, particularly for localized inflammatory swellings and infections. In TCM theory, when toxic Heat accumulates in the body, it may manifest as red, swollen, painful sores, carbuncles, and burns. Si Ji Qing is traditionally used both internally and topically for such presentations. It is commonly combined with Jin Yin Hua, Lian Qiao (if available), and Pu Gong Ying to enhance the Heat-clearing and toxicity-resolving effect. The decoction is frequently applied topically as a wash or wet compress for inflammatory skin conditions. This traditional use is based on TCM pattern differentiation and should not be equated to specific dermatologic or infectious diagnoses.

Cooling the Blood and stopping bleeding: Si Ji Qing is traditionally used to cool the Blood and stop bleeding, making it particularly suitable for patterns of Blood Heat presenting with bleeding such as hematemesis, epistaxis, and traumatic bleeding. In TCM theory, when Heat enters the Blood level, it may force the Blood to move recklessly, leading to various forms of bleeding. Si Ji Qing's cold nature is believed to cool the Blood while its astringent nature helps contain the bleeding. It is commonly combined with Sheng Di Huang, Mu Dan Pi, and Ce Bai Ye in formulas for Blood-Heat patterns with bleeding. This traditional use is based on TCM pattern differentiation and should not be equated to specific hematologic diagnoses.

Promoting tissue healing and resolving wounds: Si Ji Qing is a common folk and modern herb for promoting the healing of tissues, particularly in burns, scalds, traumatic wounds, and chronic ulcers. Its Heat-clearing, toxicity-resolving, Blood-cooling, and astringent properties are believed to reduce inflammation, protect the wound surface, and promote tissue regeneration. In folk practice, the fresh leaves are crushed and applied directly to the affected area, or the decoction is used as a wash. Modern preparations include topical solutions, ointments, and injectable extracts. This traditional use is based on TCM pattern differentiation and should not be equated to specific wound-care diagnoses.

Clearing Lung Heat and resolving phlegm: Si Ji Qing enters the Lung meridian and is traditionally used for Lung Heat patterns presenting with cough, phlegm, and sore throat. Its cold nature is believed to clear Lung Heat while its astringent nature helps reduce excessive secretions. In folk practice, the decoction is taken internally for cough with yellow phlegm and sore throat. This traditional use is based on TCM pattern differentiation and is not a treatment claim for any respiratory disease.

Classical literature references: Si Ji Qing is a relatively recent addition to the formal TCM materia medica and is not recorded in the earliest classical texts such as the Shen Nong Ben Cao Jing (Divine Farmer's Materia Medica Classic, circa 200 CE) or Li Shizhen's Ben Cao Gang Mu (Compendium of Materia Medica, 1596 CE). Its medicinal use is documented primarily in regional and folk materia medica of southern China, and it became more prominent in the mid-20th century with the development of modern herbal preparations for burns and wound care. The Ben Jing Feng Yuan and later regional references describe its use for "burns, scalds, and inflammatory swellings," and modern regional references expand on its applications for tissue healing and inflammatory conditions.

Si Ji Qing contains a range of bioactive compounds that have been the subject of pharmacological investigation. The following overview summarizes the major chemical constituents identified in the leaves of Ilex chinensis and what is currently known about them from published research.

Ursolic acid: Ursolic acid is a pentacyclic triterpenoid acid and one of the principal bioactive constituents of Ilex species, including Si Ji Qing. It is widely distributed in the plant kingdom and is among the most extensively studied pentacyclic triterpenes. Ursolic acid has been studied in pre-clinical research for its anti-inflammatory, antioxidant, hepatoprotective, antimicrobial, and antineoplastic activities. Mechanistic studies have shown that ursolic acid can inhibit pro-inflammatory cytokine production, modulate the NF-kappaB and MAPK signaling pathways, and activate the Nrf2 antioxidant pathway in cell-based and animal models. Most research on ursolic acid has been conducted on the isolated compound rather than on whole-leaf preparations, and the clinical relevance for oral TCM use is not well established.

Oleanolic acid: Oleanolic acid is another pentacyclic triterpenoid acid that is a major constituent of Si Ji Qing. It is a structural isomer of ursolic acid and shares many of its biological activities. Oleanolic acid has been studied in pre-clinical research for its anti-inflammatory, antioxidant, hepatoprotective, antimicrobial, and anti-hyperglycemic activities. Hepatoprotective effects of oleanolic acid have been documented in animal models of chemically-induced liver injury, and the compound has been investigated in some clinical studies for liver conditions. The oleanolic acid content of Si Ji Qing is influenced by the harvest time, growing conditions, and processing method.

Flavonoids: Si Ji Qing contains a range of flavonoid compounds, including quercetin, kaempferol, and their glycosides. These flavonoids contribute to the antioxidant and anti-inflammatory profile of the leaf and have been studied in pre-clinical research for antioxidant, anti-inflammatory, and vascular protective activities. Quercetin in particular has documented antioxidant and anti-inflammatory properties in cell-based and animal models. The flavonoid content of Si Ji Qing is influenced by the harvest time, growing conditions, and post-harvest handling.

Tannins: Si Ji Qing contains significant amounts of hydrolyzable and condensed tannins, which contribute to its astringent taste and its traditional wound-protecting and bleeding-stopping action. Tannins are polyphenolic compounds that can bind to proteins, forming cross-linked complexes that protect wound surfaces and reduce exudation. The tannin content is believed to underlie the traditional topical use of Si Ji Qing for burns, wounds, and chronic ulcers, where the astringent action helps protect the wound surface and reduce inflammation. The tannin content of Si Ji Qing is influenced by the harvest time and processing method.

Triterpenoid saponins: Si Ji Qing contains a range of triterpenoid saponins, which are glycosides of pentacyclic triterpenes. These saponins have been studied in pre-clinical research for anti-inflammatory, immunomodulatory, and antimicrobial activities. Triterpenoid saponins contribute to the surfactant-like foam-forming property of aqueous Si Ji Qing extracts and may contribute to the overall pharmacological profile of the herb.

Other constituents: In addition to the major constituents above, Si Ji Qing contains smaller amounts of phenolic acids, organic acids, sterols (including beta-sitosterol), and various trace elements. These minor constituents may contribute to the overall pharmacological profile of the herb but have been less extensively studied than the triterpenoids and tannins.

The compounds listed above are chemical constituents identified through phytochemical analysis. Their pharmacological activities described are based on pre-clinical studies (animal models, in-vitro experiments) and do not represent confirmed clinical effects in humans.

Si Ji Qing is used more prominently in folk and modern practice than in the canonical classical formula literature. Below are three representative traditional and modern applications that feature Si Ji Qing as a component, along with their traditional indications and the role Si Ji Qing plays in each composition.

The following section summarizes published pharmacological and pre-clinical research. Unless explicitly stated otherwise, the studies cited are animal models, in-vitro experiments, or mechanistic research — not human clinical trials. These findings should not be interpreted as evidence for clinical efficacy or as a basis for self-treatment.

Anti-inflammatory effects of ursolic and oleanolic acid: The triterpenoid constituents of Ilex chinensis, particularly ursolic acid and oleanolic acid, have been studied for their anti-inflammatory activity in cell-based and animal models. Research by Kashyap et al. (2016) reported that ursolic acid significantly reduced the production of pro-inflammatory cytokines including TNF-alpha and interleukin-6 in lipopolysaccharide-stimulated macrophages, partly through inhibition of the NF-kappaB signaling pathway (PMID: 26946749). Castellano et al. (2013) showed that oleanolic acid exerted comparable anti-inflammatory effects in macrophage models and protected against chemically-induced inflammation in animal models (PMID: 23583765). These pre-clinical findings provide mechanistic insight into the traditional use of Si Ji Qing for inflammatory swellings and burns, but their clinical relevance in humans has not been established.

Wound-healing and tissue-protective effects: The tannin- and triterpenoid-rich fraction of I. chinensis has been investigated for wound-healing activity in animal models. A study by Zheng et al. (2015) demonstrated that topical application of an aqueous extract of Si Ji Qing accelerated wound contraction and re-epithelialization in a rat excision wound model, an effect attributed in part to the astringent tannin content and the anti-inflammatory action of the triterpenoids (PMID: 26019541). More recent research by Liu et al. (2018) characterized the protective effects of Si Ji Qing extract against oxidative stress in a cell-based model of skin injury and proposed a role in tissue repair (PMID: 29524501). These findings are mechanistically consistent with the traditional topical use of Si Ji Qing for burns and wounds, but require clinical validation.

Antioxidant and hepatoprotective effects: Ursolic acid and oleanolic acid have been studied for antioxidant and hepatoprotective activities in pre-clinical models. Research by Liu et al. (2014) demonstrated that oleanolic acid protected against carbon tetrachloride-induced liver injury in rats, partly through antioxidant and anti-apoptotic mechanisms (PMID: 24650540). Subsequent work by Wang et al. (2017) showed that ursolic acid protected against oxidative stress-induced cellular damage via activation of the Nrf2/HO-1 signaling pathway (PMID: 28441971). These findings are mechanistically interesting but are derived from animal and in-vitro models and should not be extrapolated to clinical applications in humans.

Antimicrobial activity: The triterpenoid and tannin constituents of I. chinensis have been studied for antimicrobial activity. A study by Chen et al. (2016) reported that an ethanolic extract of Si Ji Qing exhibited inhibitory activity against several bacterial pathogens in in-vitro assays, an effect attributed in part to the triterpenoid and tannin content (PMID: 27474189). While these findings provide mechanistic insight into the traditional use of Si Ji Qing as a Heat-clearing and toxicity-resolving herb, their clinical relevance for human infections has not been established.

What the research does NOT show: Despite promising pre-clinical signals, the research on Si Ji Qing and its active compounds does NOT demonstrate conclusive clinical efficacy for any specific disease in humans. There is no robust evidence from large-scale, randomized, placebo-controlled clinical trials that Si Ji Qing can treat, cure, or prevent burns, infections, inflammatory disorders, or any other medical condition. The translation from animal models to human clinical relevance is uncertain. This page does not endorse Si Ji Qing as a treatment for any condition.

Important: All pharmacological effects described above are based on pre-clinical studies (animal models, in-vitro experiments, or mechanistic research). They do not constitute evidence of clinical efficacy in humans. This section is provided for educational context and should not be used as a basis for treatment decisions.

General safety profile: Si Ji Qing is widely used in folk and modern TCM practice and is generally considered to have a favorable safety profile when used appropriately at standard doses, particularly when applied topically. However, like all herbal products, it is not free of risk. The information below reflects what is currently known from published literature, pharmacopoeial standards, and traditional clinical experience.

Spleen-Stomach deficiency-cold: In traditional TCM theory, Si Ji Qing is bitter, astringent, and cold in nature. Individuals with Spleen-Stomach deficiency-cold — characterized by poor appetite, abdominal coldness, loose stools, a pale tongue with white coating, and a deep, slow pulse — should use Si Ji Qing with caution, as its cold nature may further weaken digestive function. Prolonged internal use or use at high doses may cause or worsen diarrhea and abdominal discomfort in such individuals. This caution is based on traditional TCM theory rather than modern clinical evidence.

Pregnancy and lactation: Si Ji Qing is traditionally considered cold in nature and is also said to cool the Blood. Although rigorous human safety data in pregnancy are lacking, internal use during pregnancy should be avoided or undertaken only under the direct supervision of a qualified healthcare professional, particularly in the first trimester. Topical use on intact skin is generally considered low risk. Self-administration of concentrated Si Ji Qing extracts or injectable preparations during pregnancy is not recommended.

Anticoagulant interactions: Because Si Ji Qing is traditionally said to cool the Blood and stop bleeding, and because tannin constituents can affect platelet function and blood coagulation in pre-clinical studies, there is a theoretical risk of interaction with anticoagulant or antiplatelet medications (such as warfarin, clopidogrel, or aspirin). The tannin content may also bind to certain orally administered medications in the gastrointestinal tract, reducing their absorption. Human interaction data for whole-leaf Si Ji Qing are very limited. Individuals taking anticoagulant or antiplatelet medications should consult a qualified healthcare professional before using Si Ji Qing, particularly in concentrated forms.

Astringent action and constipation: The tannin content of Si Ji Qing contributes to its astringent action, which is valued for wound protection and bleeding control but may, with prolonged internal use at high doses, cause or worsen constipation in susceptible individuals. Individuals prone to constipation or with patterns of intestinal dryness should use Si Ji Qing internally with caution and only in combination with appropriate moistening and harmonizing herbs.

Drug interactions: Pre-clinical data suggest that triterpenoid constituents of Si Ji Qing, particularly ursolic acid and oleanolic acid, may affect the activity of hepatic cytochrome P450 enzymes (notably CYP3A4 and CYP2C9), which could theoretically alter the metabolism of drugs processed through these pathways. The tannin content may also bind to certain orally administered medications in the gastrointestinal tract, reducing their absorption. Clinical interaction data for whole-leaf Si Ji Qing are very limited. Consult a qualified healthcare professional before combining Si Ji Qing with any prescription medications.

This platform provides educational information about traditional Chinese medicine herbs. It does not recommend, endorse, or prescribe the use of Si Ji Qing or any other herbal product for the treatment of any medical condition. All decisions regarding herbal use should be made in consultation with a qualified healthcare provider.