Chai Hu
StarBupleurum falcatum
Synonyms: Bupleurum falcatum var. genuinum, Bupleurum falcatum subsp. eufalcatum
☯ TCM Properties
Resolves Shao Yang disorders and reduces fever; Spreads Liver Qi and relieves Stagnation; Raises Yang Qi (Clear Qi of the Stomach and Gallbladder); Disperses Wind-Heat and resolves Phlegm
Traditional Chinese Uses
Chai Hu (bupleurum root) is a cool, acrid herb with an ascending, dispersing nature that makes it uniquely suited to resolving issues at the Shao Yang level of the body. It is used to harmonize the Shao Yang for the alternating fever and chills of Shao Yang syndrome, to spread Liver Qi for emotional depression, chest and flank tightness, and menstrual irregularities, and to raise sinking Spleen Qi for organ prolapse and chronic diarrhea. It is the primary herb in many of the most frequently used formulas in Chinese medicine.
Western Herbalism Properties
Used In Formulas (5)
Gallery
Botanical Description
Bupleurum falcatum is a perennial herb in the carrot family (Apiaceae), growing 30-80 cm tall from a woody taproot. Stems are slender, branched, and somewhat woody at the base. Leaves are narrow, sickle-shaped (falcate), and parallel-veined, resembling grass blades. The inflorescence is a compound umbel of small yellow flowers. Fruits are oval to oblong, ribbed, and about 3-4 mm long. The root is brown externally and pale inside with a distinctive bitter taste and slight aroma.
Dry hillsides, grasslands, scrubland, forest margins, and rocky slopes; native to temperate Eurasia from Europe to eastern Asia, including China, Japan, and Korea.
Bupleurum falcatum is a widespread species across Eurasia. While some Bupleurum species in China have faced collection pressure due to high medicinal demand, this species remains relatively common. Sustainable harvesting practices are recommended.
Active Constituents
Saikosaponin a
Oleanane-type triterpenoid saponinConcentration: One of the principal saikosaponins; total saikosaponins ~ up to several % of root
Major bioactive saponin with anti-inflammatory, hepatoprotective and antipyretic activity. Modulates NF-κB and MAPK signaling and contributes to the fever-reducing and Liver-protecting actions of Radix Bupleuri.
Saikosaponin d
Oleanane-type triterpenoid saponinConcentration: Principal saikosaponin and key quality marker
The most pharmacologically potent saikosaponin. Exhibits strong anti-inflammatory (glucocorticoid-like), hepatoprotective, antifibrotic, antiviral and antitumor activity; also the constituent most associated with dose-dependent hepatotoxicity at high exposure.
Saikosaponin c
Oleanane-type triterpenoid saponinConcentration: One of the three most common saikosaponins
Triterpenoid saponin with antiviral, anti-inflammatory and endothelial/anti-atherogenic effects; part of the saikosaponin fraction responsible for the herb's Shao-Yang harmonizing and Liver-coursing actions.
Bupleuran 2IIc
Pectic polysaccharideConcentration: Major water-soluble polysaccharide of the root
Immunomodulatory and anti-ulcer pectic polysaccharide. Activates the complement system and mucosal immunity and protects the gastric mucosa in experimental models.
Bupleurum essential oil (incl. terpenoid volatiles)
Volatile terpenoid oilConcentration: Small volatile fraction of the root
Essential-oil fraction implicated in the antipyretic (fever-reducing) and antimicrobial effects traditionally used for exterior wind-heat and Shao-Yang fevers.
Rutin
Flavonoid glycosideConcentration: Most common flavonoid of the genus
Antioxidant and vascular-protective flavonoid contributing to anti-inflammatory and capillary-stabilizing activity of the whole extract.
α-Spinasterol
PhytosterolConcentration: Minor sterol constituent
Plant sterol with anti-inflammatory and antinociceptive activity that contributes to the overall anti-inflammatory profile of Bupleurum root.
⚠ Drug Interactions
Interferon-alfa
The Bupleurum-containing formula sho-saiko-to (Xiao Chai Hu Tang) has been associated with interstitial pneumonitis, and multiple case reports describe acute pneumonitis when it is combined with interferon in patients with chronic hepatitis. An immune-mediated hypersensitivity mechanism (positive lymphocyte stimulation tests) is proposed.
Clinical note: Bupleurum-based formulas such as sho-saiko-to should not be combined with interferon; onset is fever, dry cough and dyspnea with diffuse pulmonary infiltrates, responsive to corticosteroids on withdrawal.
Hepatotoxic drugs (e.g., high-dose acetaminophen, methotrexate)
High or prolonged doses of saikosaponins (notably saikosaponin d) can themselves cause hepatocellular injury; concurrent use with other hepatotoxic agents may be additive.
Clinical note: Avoid large or prolonged doses in patients on hepatotoxic drugs or with existing liver disease; monitor transaminases.
Corticosteroids (e.g., prednisolone)
Saikosaponins exhibit glucocorticoid-potentiating activity and can prolong/enhance endogenous and exogenous corticosteroid effects, theoretically increasing both efficacy and steroid-related adverse effects.
Clinical note: Consider when patients combine Bupleurum preparations with systemic corticosteroids; clinical significance not well quantified.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 3-12 g | daily | — | adult | Lower doses (3-6 g) to raise Yang; higher doses (up to 12 g) to resolve Shao Yang and reduce fever. Use vinegar-fried to spread Liver Qi. |
Preparation Methods
Raw (sheng Chai Hu) decoction
Parts: root
Dried root decocted, typically 3-10 g per day. The raw herb is used to resolve Shao-Yang disorders and reduce fever and to disperse wind-heat; higher relative doses favor the exterior-releasing/fever-reducing action.
Vinegar-processed (cu Chai Hu)
Parts: root
Root slices stir-fried with rice vinegar. Vinegar processing directs the herb more strongly to the Liver channel and enhances its Liver-coursing, Qi-regulating action for Liver-Qi stagnation.
Stir-fried with turtle blood (bie xue chao Chai Hu)
Parts: root
Root processed with soft-shelled turtle blood to moderate its ascending/dispersing nature and add a Yin-nourishing quality; used for steaming-bone tidal fever and deficiency-heat patterns.
Clinical Studies
Genus Bupleurum: a review of its phytochemistry, pharmacology and modes of action
Reviews the phytochemistry (over 120 saikosaponins plus lignans, flavonoids, polyacetylenes, essential oils, polysaccharides) and pharmacology of the genus Bupleurum, detailing anti-inflammatory, hepatoprotective, antipyretic, antiviral, immunomodulatory and antitumor actions and their mechanisms.
A systematic review of the active saikosaponins and extracts isolated from Radix Bupleuri and their applications
Systematic analysis of saikosaponin A and D and Radix Bupleuri extracts, documenting anti-inflammatory, antitumor, antiviral, anti-allergic, immunoregulatory and neuroregulatory activities via NF-κB and MAPK pathways, together with 15 approved clinical preparations and hepatotoxicity as the principal safety concern.
Historical Texts
Shennong Bencao Jing (Divine Farmer's Materia Medica)
Eastern Han dynasty, c. 200 CEShang Han Lun (Treatise on Cold Damage), Zhang Zhongjing
Eastern Han dynasty, c. 200 CEBencao Gangmu (Compendium of Materia Medica), Li Shizhen
Ming dynasty, 1596References
- Ashour ML, Wink M. Genus Bupleurum: a review of its phytochemistry, pharmacology and modes of action . Journal of Pharmacy and Pharmacology 63(3):305-321 (2011) [DOI]
- Yuan B, Yang R, Ma Y, Zhou S, Zhang X, Liu Y. A systematic review of the active saikosaponins and extracts isolated from Radix Bupleuri and their applications . Pharmaceutical Biology 55(1):620-635 (2017) [DOI]
- Chinese Pharmacopoeia Commission. Chaihu (Bupleuri Radix), Pharmacopoeia of the People's Republic of China, Vol. I . China Medical Science Press (2020) [DOI]
- Bensky D, Clavey S, Stoger E. Chinese Herbal Medicine: Materia Medica, 3rd ed. . Eastland Press, Seattle (2004) [DOI]
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.
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