Huang Qin
StarScutellaria baicalensis Georgi
Traditionally used for
- Cough & breathing
- Colds & fever
- Digestion
- Bowel health
- Urinary & fluids
- Liver & jaundice
☯ TCM Properties
Clears Heat and dries Dampness; Purges Fire and Resolves Toxicity; Stops Bleeding; Calms the Fetus
Traditional Chinese Uses
Huang Qin (Chinese skullcap root, baical skullcap) is one of the most important and widely prescribed Heat-clearing herbs in Chinese medicine. It drains Fire and Damp-Heat from the Upper Burner, making it a primary herb for febrile illness, Lung Heat with cough and yellow phlegm, and Upper Burner inflammation. It also clears Damp-Heat from the Stomach, Intestines, and Gallbladder, addressing dysentery, jaundice, and Damp-Heat diarrhea. Additionally, it cools the Blood to stop bleeding and calms the fetus in heat-related threatened miscarriage.
Western Herbalism Properties
Pharmacological Effects
- Antimicrobial and antiviral: Decoction broadly antibacterial in vitro (streptococci, pneumococcus, meningococcus, S. aureus, dysentery/typhoid bacilli, P. aeruginosa, etc.), baicalin the main active; active against skin fungi; crude extract and baicalin inhibited HIV antigen expression and reverse transcriptase in cell culture; a trihydroxy-methoxyflavone suppressed influenza A and B in MDCK cells.
- Antiallergic: Baicalin and baicalein inhibited allergic asthma and Schultz-Dale reactions in sensitized guinea pigs (baicalein stronger); several flavones inhibited mast-cell and basophil histamine release; baicalein inhibited hyaluronidase and basophil growth in vitro.
- Antiinflammatory: Baicalin, baicalein and wogonin reduced vascular permeability and paw edema in rodents and adjuvant arthritis lesions; baicalein inhibited 5-lipoxygenase (LTC4 IC50 9.5 µM); flavonoids reduced IL-1, PGE2 and LTB4 while stimulating gingival fibroblasts.
- Antipyretic: Oral extract dose-dependently lowered rectal temperature in rats via cutaneous vasodilation; baicalin 4.5 mg/kg comparable to 100 mg/kg coantipyrine in febrile rats, without lowering normal temperature.
- Cardiovascular and lipid: Various extracts and baicalin (10-20 mg/kg i.v.) lowered blood pressure in dogs, including renal/neurogenic hypertensive models; flavones inhibited platelet aggregation, fibrin formation, lipid peroxidation and vascular smooth muscle proliferation, and improved lipid profiles in rats.
- Hepatoprotective and choleretic: Root and baicalin protected against CCl4 and galactosamine liver injury; baicalin raised strychnine LD50 2.5-fold; decoction, extracts and baicalin increased bile secretion and lowered bilirubin in bile-duct-ligated rabbits.
- Sedative and diuretic: Sedation in mice, dogs and rabbits (baicalin 500-1000 mg/kg i.p. in mice); extracts, baicalin, baicalein and wogonin were diuretic in rabbits, mice and dogs.
Source: Zhu YP. Chinese Materia Medica: Chemistry, Pharmacology and Applications. Harwood Academic, 1998, p. 127.
Used In Formulas (166)
Relationships
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Botanical Description
Scutellaria baicalensis is a herbaceous perennial in the Lamiaceae, native to northeastern China, Mongolia, southeastern Siberia, Korea and parts of Japan, where it grows on dry, sunny grassy slopes, rocky open ground and gravelly riverbanks. Plants form clumps 30-60 cm tall from a stout, woody, branching taproot that is bright yellow inside. The four-angled stems are erect to ascending and bear opposite, narrowly lanceolate to linear leaves 2-5 cm long, with entire to faintly toothed margins and short petioles. From early summer the species produces showy, one-sided racemes of violet-blue to purplish, two-lipped tubular flowers about 2-3 cm long, the upper lip helmet-shaped and the lower lip three-lobed. The fruits are small, dark-coloured nutlets enclosed in the persistent calyx, whose upper lip bears the characteristic scutellate appendage of the genus. The roots are harvested in autumn of the third or fourth year.
Active Constituents
Baicalin
Flavone-7-O-glucuronideConcentration: Not less than 9.0% of dried root (Chinese Pharmacopoeia marker)
The dominant and defining constituent of the root, with well-characterised anti-inflammatory, antibacterial, antiviral, antioxidant, hepatoprotective and antipyretic activity. It suppresses inflammatory cytokines (IL-6, TNF-alpha, IL-1beta) and mediates much of the herb's heat-clearing, fire-purging action.
Baicalein
Flavone (aglycone of baicalin)Concentration: Approx. 0.5-5% of dried root (increases with processing)
The lipophilic aglycone with strong antioxidant, anti-inflammatory, 12-lipoxygenase-inhibiting and antitumour activity; more readily absorbed than baicalin and a major driver of the root's pharmacology.
Wogonoside
Flavone-7-O-glucuronideConcentration: Approx. 2-4% of dried root
A glucuronide flavone contributing anti-inflammatory and anti-allergic effects; hydrolysed to wogonin in the gut for absorption.
Wogonin
Methoxylated flavoneConcentration: Approx. 0.1-1% of dried root
A lipophilic flavone with anxiolytic, anti-inflammatory, neuroprotective and antitumour activity; modulates GABA-A receptors and NF-kB signalling.
Oroxylin A
Methoxylated flavoneConcentration: Trace to ~0.3% of dried root
A minor flavone with anti-inflammatory, neuroprotective and P-glycoprotein-modulating activity, contributing to the overall antioxidant and anti-tumour profile.
Skullcapflavone II
Polymethoxylated flavoneConcentration: Trace amounts
A characteristic Scutellaria flavone with anti-inflammatory and antifibrotic activity, of interest as a chemotaxonomic marker.
⚠ Drug Interactions
Rosuvastatin
Baicalin inhibits/modulates the hepatic uptake transporter OATP1B1 (SLCO1B1). In a controlled human study it reduced rosuvastatin plasma concentrations in carriers of the OATP1B1*1b haplotype, with no change in *15/*15 carriers, indicating a genotype-dependent herb-drug interaction.
Clinical note: Separate administration and monitor lipid response; the effect can lower rosuvastatin efficacy in susceptible patients.
Cyclosporine (ciclosporin)
Multiple-dose baicalin induces intestinal P-glycoprotein and modulates CYP3A, decreasing the oral bioavailability of ciclosporin in animal studies. Given ciclosporin's narrow therapeutic index, a clinically meaningful reduction in blood levels is plausible.
Clinical note: Avoid concurrent use in transplant patients or monitor ciclosporin trough levels closely if unavoidable.
CYP3A4 substrates (e.g. midazolam, nifedipine)
Baicalin inhibits CYP3A activity and displaces protein-bound drugs in rat models, raising exposure of CYP3A substrates such as midazolam and nifedipine. Human relevance is likely but not fully quantified.
Clinical note: Use caution and monitor for exaggerated effects of narrow-index CYP3A substrates.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 3–10 g | Daily | — | — | 中国药典 2020 【用法与用量】3～10g。 【性味与归经】苦，寒。归肺、胆、脾、大肠、小肠经。 — Chinese Pharmacopoeia 2020, quoted verbatim; route and cautions preserved. Replaces a cleared category-filler value. |
Preparation Methods
Raw (sheng) dried root, decoction
Parts: Dried root
Typical dose 3-10 g. The raw root most strongly clears heat, drains fire and resolves toxicity, especially in the upper burner (lung heat, high fever). Roots are briefly steamed or boiled during processing to inactivate endogenous beta-glucuronidase, preventing enzymatic hydrolysis of baicalin and preserving potency.
Wine-fried (jiu chao) root
Parts: Dried root
Stir-frying with wine directs the action upward to clear heat in the upper body and lungs and is traditionally used to clear heat in the upper burner and during pregnancy support formulas.
Dry-fried (chao) root
Parts: Dried root
Plain dry-frying moderates the intensely cold nature so it is gentler on the Spleen and Stomach, favoured for damp-heat of the middle burner and to calm a restless fetus.
Charred root (Huang Qin Tan)
Parts: Dried root
Charring enhances the hemostatic action, used for bleeding due to heat such as hemoptysis or uterine bleeding. Traditionally, hollow older roots (Ku Qin) are chosen to clear Lung heat and solid younger roots (Zi Qin) to clear heat of the lower burner and large intestine.
Dui Yao — Herb Pairs
The classical two-herb combinations this herb appears in, each with an action neither herb has alone.
Together they clear heat from the intestines while softening the Liver and relieving spasm, treating heat diarrhea or dysentery with abdominal pain.
Core pair of a classical formula — Huang Qin Tang, Shang Han Lun (Zhang Zhongjing)
Together they clear heat and strengthen the Spleen to calm a restless fetus.
Traditionally attributed to Zhu Danxi as a key pairing for calming the fetus when heat and Spleen deficiency are present.
Named pairing — Zhong Yao Xue, national textbook (pei wu section for Huang Qin)
Together one vents pathogens from the shaoyang exterior while the other clears heat from within, harmonizing shaoyang and resolving alternating chills and fever.
Core pair of a classical formula — Xiao Chai Hu Tang, Shang Han Lun (Zhang Zhongjing)
Clears and transforms phlegm-heat while draining fire from the lungs at its source.
Phlegm-heat cough. Dan Nan Xing is Tian Nan Xing processed with bile, which moderates its toxicity; the raw root is toxic.
Core pair of a classical formula — Qing Qi Hua Tan Wan, Yi Fang Kao (Wu Kun)
Together they strongly clear heat, drain fire and dry damp across the upper and middle burners, and resolve heat toxin.
Core pair of a classical formula — Ge Gen Huang Qin Huang Lian Tang, Shang Han Lun (Zhang Zhongjing)
Together they drain excess fire from the liver and gallbladder and clear damp-heat, extending the bitter-cold draining action upward and downward along the channel.
Core of the formula for liver-gallbladder fire (headache, red eyes, bitter taste, hypochondriac pain) or damp-heat pouring downward. Very bitter and cold; not for prolonged use or spleen deficiency.
Core pair of a classical formula — Long Dan Xie Gan Tang, Yi Fang Ji Jie (Wang Ang)
Together they clear and vent damp-heat from the Gallbladder and shaoyang, resolving alternating chills and fever with bitter taste and nausea.
Core pair of a classical formula — Hao Qin Qing Dan Tang, Chong Ding Tong Su Shang Han Lun (Yu Genchu; revised He Lianchen)
Evidence Tier
Moderate evidence · 2 studiesRecorded studies by study design, strongest design at the top. This is a study-design tier only, not a GRADE rating: it does not weigh risk of bias, consistency or precision.
Systematic review / meta-analysis
0
Randomized controlled trial
1
1 verified · 0 unverified
Other clinical trial
0
Observational / case report
0
In vitro / animal
0
Other / unclassified
1
1 verified · 0 unverified
Verified: design read from PubMed for a DOI that resolves to the cited paper Unverified: taken from the study's recorded description
Clinical Studies
The Effect of Herbal Medicine Baicalin on Pharmacokinetics of Rosuvastatin, Substrate of Organic Anion-transporting Polypeptide 1B1
In 18 healthy volunteers stratified by OATP1B1 haplotype, baicalin significantly reduced rosuvastatin plasma concentrations in OATP1B1*1b carriers but not in *15/*15 carriers, demonstrating a clinically relevant, genotype-dependent transporter-mediated herb-drug interaction.
Old formula, new Rx: The journey of PHY906 as cancer adjuvant therapy
Reviews the development of PHY906 (Huang-Qin-Tang, in which Scutellaria baicalensis is the sovereign herb) as a standardised adjuvant that reduces chemotherapy-induced gastrointestinal toxicity in clinical trials while enhancing anti-tumour activity, illustrating the modern evidence base for Huang Qin.
⚠ Safety & Contraindications
Contraindications
It is not suitable for patients with deficiency-cold of the spleen and stomach since it is bitter in flavor and cold in nature and easy to damage the stomach.
Source: Xi S, Gong Y. Essentials of Chinese Materia Medica and Medical Formulas. Academic Press/Elsevier, 2017, pp. 46–50.
Side Effects
- Rare gastric discomfort and diarrhea with oral crude preparations or injected baicalin/baicalein; otherwise no side effects reported.
Source: Zhu YP. Chinese Materia Medica: Chemistry, Pharmacology and Applications. Harwood Academic, 1998, p. 127.
Historical Texts
Shennong Bencao Jing (Divine Farmer's Materia Medica)
Eastern Han, c. 200 CEShang Han Lun (Treatise on Cold Damage), Zhang Zhongjing
Eastern Han, c. 200 CEReferences
- Fan L, Zhang W, Guo D, Tan ZR, Xu P, Li Q, et al.. The Effect of Herbal Medicine Baicalin on Pharmacokinetics of Rosuvastatin, Substrate of Organic Anion-transporting Polypeptide 1B1 . Clinical Pharmacology & Therapeutics (2008) [DOI]
- Zhou X, Fu L, Wang P, Yang L, Zhu X, Li CG. Drug-herb interactions between Scutellaria baicalensis and pharmaceutical drugs: Insights from experimental studies, mechanistic actions to clinical applications . Biomedicine & Pharmacotherapy (2021) [DOI]
- Zhao Q, Chen XY, Martin C. Scutellaria baicalensis, the golden herb from the garden of Chinese medicinal plants . Science Bulletin (2016) [DOI]
- Liu SH, Cheng YC. Old formula, new Rx: The journey of PHY906 as cancer adjuvant therapy . Journal of Ethnopharmacology (2012) [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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