Bupleurum
ApiaceaeBupleurum chinense
Also known as: Chai Hu, Thorowax Root, Hare's Ear Root
clinical_notes Clinical Summary
Bupleurum (Bupleurum chinense, Chai Hu) is one of the most clinically important herbs in Chinese medicine, the sovereign herb of Xiao Chai Hu Tang, used to harmonize Shaoyang, soothe Liver Qi stagnation, and raise sinking Qi.
Its triterpenoid saikosaponins are well studied for hepatoprotective, anti-inflammatory, antiviral, and antidepressant activity.
It requires respectful prescribing: high doses or long-term unsupervised use, especially in combination with interferon or in severe liver disease, carries documented hepatotoxicity risk.
Pregnancy Safety
Avoid during pregnancy due to dispersing action, uterine-stimulant potential, and insufficient safety data.
Lactation Safety
Avoid; no adequate lactation safety data.
warning Contraindications
- Pregnancy (avoid)Theoretical
- Lactation (avoid)Theoretical
- Active severe liver disease (caution)Clinically Proven
- Yin deficiency or rising Liver Yang (TCM) (caution)Theoretical
- Interferon therapy (especially in chronic hepatitis C) (contraindicated)Clinically Proven
- Autoimmune disease (SLE, RA, MS) (caution)Theoretical
vital_signs Clinical Profile
Primary Indications
- check_circle Alternating fever and chills (Shaoyang)
- check_circle Liver Qi stagnation
- check_circle Chronic hepatitis
- check_circle Costal/hypochondriac pain
- check_circle Uterine or rectal prolapse (with Qi-tonics)
- check_circle Irregular menstruation
- check_circle Depression with irritability
- check_circle PMS
Therapeutic Actions
System Affinities
- check_circle hepatic system
- check_circle Shaoyang channel
- check_circle immune system
- check_circle gastrointestinal system
labs Active Constituents
Triterpenoid saikosaponins
Saikogenins
Bupleurans
Flavonoids
Volatile oil
Phytosterols
Polyacetylenes
history_edu Traditional Use
Traditional Chinese Medicine (TCM)
柴胡 (Chái Hú)
Nature: cool
- Shaoyang syndrome (alternating fever and chills)
- Liver Qi stagnation
- Sinking of Spleen Qi (prolapse, chronic diarrhea)
- Irregular menstruation
Key Shaoyang-channel herb; harmonizes interior and exterior, spreads Liver Qi, and raises Yang. Sovereign herb of Xiao Chai Hu Tang. First recorded in Shennong Ben Cao Jing (~200 BCE).
Traditional Uses Across Healing Systems
While many herbs lack controlled clinical trials, centuries of traditional practice across cultures provide valuable insight into their therapeutic applications.
Harmonizes Shaoyang, soothes Liver Qi, raises clear Yang; used for alternating fever and chills, chest/hypochondriac distention, irritability, irregular menses, and prolapse.
Sovereign herb in Xiao Chai Hu Tang (Minor Bupleurum Decoction).
Core herb in Sho-saiko-to and related formulas used for chronic hepatitis and inflammatory liver disease.
Clinical use carefully regulated after adverse events with interferon co-therapy.
spa Parts Used
root
- Shaoyang syndrome
- Liver Qi stagnation
- Hepatitis
- Depression
Roots are dug in spring or autumn, cleaned, and dried. Decocted alone or in formula; alcohol extraction yields a more hepatotoxic fraction than water extraction.
shield Safety
Contraindications — Evidence Basis
Pregnancy
Possible uterine stimulation; hepatotoxicity at higher doses; classically avoided.
Lactation
Insufficient safety data.
Active severe liver disease
Saikosaponin D can induce hepatocyte injury at high doses; hepatotoxic case reports exist with Sho-saiko-to and injectable preparations.
Yin deficiency or rising Liver Yang (TCM)
Classical contraindication due to light, dispersing upward-moving action.
Interferon therapy (especially in chronic hepatitis C)
Sho-saiko-to + interferon combination has caused interstitial pneumonitis, some fatal, in Japan.
Autoimmune disease (SLE, RA, MS)
Immunostimulant polysaccharides may aggravate autoimmune activity.
Monitoring Parameters
Monitor during use, especially with prolonged or high-dose therapy.
Liver enzymes (ALT, AST)
Baseline and every 3 months with ongoing useSaikosaponin D can be hepatotoxic at high doses; documented hepatitis cases with long-term Sho-saiko-to use.
flagThreshold: ALT/AST >3x ULN: discontinue and reassess.
Toxicity
Crude saikosaponin oral LD50 in mice = 4.7 g/kg; high human doses (>15 g/day of crude root for extended periods) linked to hepatic injury.
Nausea, lassitude, bowel changes at high doses; hepatitis, elevated LFTs, interstitial pneumonitis reported (Sho-saiko-to).
Discontinue immediately; supportive liver care; corticosteroids for pneumonitis if severe.
Adverse Effects
CYP Metabolism
Saikosaponins can modulate CYP3A4 and P-glycoprotein in vitro; caution with narrow-therapeutic-index CYP3A4 substrates.
swap_horiz Interactions
Interferon-alpha
Class: Immunomodulator (antiviral)
Combined use of Bupleurum-containing Sho-saiko-to (Xiao Chai Hu Tang) with interferon-alpha is linked to a sharply elevated incidence of interstitial pneumonitis. Frequency of drug-induced pneumonitis was 0.7% with Sho-saiko-to alone, 0.5% with interferon alone, but 4.0% when given together; several deaths have been reported.
Contraindicated combination. Do not co-administer Bupleurum or Sho-saiko-to with interferon therapy for chronic hepatitis. Discontinue Bupleurum before initiating interferon.
Tolbutamide
Class: Sulfonylurea antidiabetic
In animal studies, Sho-saiko-to (major ingredient Bupleurum) reduced the bioavailability of tolbutamide, likely through induction of CYP2C9-mediated metabolism. This may reduce hypoglycemic efficacy.
Monitor fasting glucose and HbA1c when Bupleurum-containing formulas are started or stopped. Consider dose adjustment of tolbutamide if glycemic control worsens.
CYP3A4 substrates (simvastatin, tacrolimus, nifedipine)
Class: CYP3A4 substrates
Total saikosaponins at 10-15 microg/mL reduce CYP3A4 mRNA and protein expression in HepaRG cells, suggesting that Bupleurum extracts inhibit CYP3A4. Co-administration may elevate plasma concentrations of narrow-index CYP3A4 substrates.
For drugs with a narrow therapeutic index (tacrolimus, cyclosporine, simvastatin), monitor plasma drug levels or clinical response when Bupleurum is added. Adjust dose as needed.
Caffeine and other CYP1A2 substrates (theophylline, clozapine)
Class: CYP1A2 substrates
Total saikosaponins upregulate CYP1A2 mRNA and protein expression in HepaRG cells at 15 microg/mL. Induction of CYP1A2 may reduce plasma concentrations of CYP1A2 substrates.
Monitor clinical efficacy of theophylline or clozapine when Bupleurum is co-administered; drug level checks and dose up-titration may be needed.
Corticosteroids (prednisone, dexamethasone)
Class: Glucocorticoid
Saikosaponins exert glucocorticoid-like anti-inflammatory effects and have been shown to potentiate steroid activity via hepatic metabolism modulation. In practice this can augment anti-inflammatory response but also adverse effects.
When combining, monitor for hypokalemia, hyperglycemia, and Cushingoid features. Taper steroids carefully if Bupleurum is discontinued.
Acetaminophen (paracetamol) and other hepatotoxic drugs
Class: Analgesic/antipyretic
Bupleurum/saikosaponins have been implicated in idiosyncratic drug-induced liver injury, and overdose-related hepatotoxicity is documented. Co-administration with known hepatotoxic drugs may increase cumulative liver injury risk.
Avoid high-dose or prolonged Bupleurum use in patients on chronic acetaminophen, methotrexate, isoniazid, or statins. Monitor LFTs monthly while co-administered.
Warfarin
Class: Anticoagulant (vitamin K antagonist)
Bupleurum modulates CYP3A4 and CYP1A2 (pathways responsible for R-warfarin metabolism). Directionally opposing effects (CYP3A4 inhibition + CYP1A2 induction) make net impact unpredictable.
If combination is unavoidable, monitor INR weekly for 2-4 weeks after starting or discontinuing Bupleurum. Warn patient to report bruising or bleeding.
hub Combinations
Synergistic pairings can enhance therapeutic outcomes, while knowing suitable substitutes helps when specific herbs are unavailable or contraindicated.
Classical Formulas
4Chinese Skullcap
Strong EvidenceCore pair in Xiao Chai Hu Tang. Bupleurum resolves Shaoyang; Scutellaria clears heat; together they harmonize exterior-interior.
Sho-saiko-to (pair at core) reduces liver enzymes in chronic viral hepatitis.
Dong Quai
Moderate EvidencePair in Xiao Yao San for Liver Qi stagnation with Blood deficiency; regulates menstruation and mood.
Xiao Yao San widely used for premenstrual syndrome and depression with clinical support.
Magnolia Bark
Traditional UsePair in Chai Hu Shu Gan San and related anti-anxiety formulas; both move stagnant Qi.
Empirical TCM use for Liver Qi stagnation with chest/abdominal distention.
White Peony
Strong EvidenceClassic pair in Xiao Yao San and Chai Hu Shu Gan San; Bupleurum disperses Liver Qi while White Peony nourishes Liver Blood, preventing Qi dispersion from consuming Yin.
Xiao Yao San shows efficacy in PMS, perimenopausal symptoms, and depression in multiple RCTs.
Synergistic Combinations
1Licorice Root
Traditional UseLicorice harmonizes formulas, mitigates the bitterness and dispersing action of Bupleurum, and may reduce hepatotoxicity risk.
Standard pairing in Xiao Chai Hu Tang and many other formulas.
science Studies
Bupleurum chinense ameliorates metabolic-associated fatty liver disease by modulating Sirtuin 6
In VivoThis in vivo study used a high-fat diet murine model of metabolic-associated fatty liver disease (MAFLD) to investigate Bupleurum chinense (Bc) decoction effects over 4 weeks at doses of 0.325, 0.65, and 1.3 g/kg/day. Bc significantly reduced lipid accumulation and oxidative stress, with the highest dose showing marked reductions in circulating triglycerides, ALT, and AST comparable to pioglitazone. Transcriptomic analysis identified SIRT6 as the central mediator, as Bc upregulated SIRT6 and its deacetylase activity, subsequently promoting fatty acid beta-oxidation and antioxidant gene expression. Cell studies confirmed SSc (25 µM) improved lipid deposition and redox imbalance in MAFLD hepatocyte models.
A systematic review of the active saikosaponins and extracts isolated from Radix Bupleuri and their applications
Systematic ReviewThis comprehensive systematic review synthesized the pharmacological evidence for saikosaponins (especially SSa and SSd) derived from Radix Bupleuri (Bupleurum chinense). The review documented anti-inflammatory activity through NF-kB and MAPK pathway inhibition, hepatoprotective effects via inhibition of hepatic stellate cell activation, and significant antiviral properties against hepatitis viruses. Liver fibrosis models showed SSa could downregulate BMP-4 and inhibit stellate cell proliferation. The review also highlighted dose-dependent hepatotoxicity risk with high-dose preparations and noted that the maximum tolerated dose is critical for safe clinical use.
medication Dosing
decoction
3-12 g dried root
1x/day (divided)
TCM Pharmacopoeia dose. Use lower range for Liver Qi smoothing; higher for fever.
tincture
1-3 mL (1:5, 45% ethanol)
2-3x/day
Alcohol extractions are more hepatotoxic than water; prefer lower-alcohol or aqueous forms for long-term use.
capsule
500-1500 mg root powder or standardized extract
2-3x/day
Short courses preferred.
Disclaimer: This information is largely AI-generated and reviewed by human experts at Evara Health. It is intended for educational and clinical reference purposes only and should not replace professional medical advice.
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