Qian Hu
StarPeucedanum praeruptorum Dunn
Traditionally used for
- Cough & breathing
☯ TCM Properties
Descends Qi and Transforms Phlegm; Disperses Wind-Heat; Resolves Phlegm and Stops Cough
Traditional Chinese Uses
Qian Hu (hogfennel root) is a cool, bitter, pungent herb with a dual action on the Lungs: it redirects rebellious Lung Qi downward to stop cough and wheezing, while also transforming Phlegm-Heat. It is appropriate for coughs accompanied by yellow, thick sputum and chest tightness, as well as for early stages of Wind-Heat invasion where these Lung symptoms are present. It pairs well with other Phlegm-clearing and Wind-Heat-dispersing herbs.
Western Herbalism Properties
Relationships
Full-screen graph →Click a node for details · double-click to expand it · Ctrl/⌘ + scroll or two fingers to zoom and pan.
Botanical Description
Peucedanum praeruptorum is a perennial herb in the Apiaceae family, native to central and southern China, where it grows on grassy mountain slopes and at the edges of forests. The plant grows 60-100 cm tall from a stout, cylindrical, somewhat conical taproot 4-15 cm long with a knobby crown bearing the remains of leaf bases. The stem is erect, finely ridged, and branched in the upper portion. The basal and lower stem leaves are large, triangular-ovate in outline, and two-to-three times ternately or pinnately compound, with serrate, ovate to lanceolate leaflets. Small white flowers are borne in compound umbels 4-8 cm across in summer, followed by ovoid, slightly winged schizocarp fruits. In TCM, the dried root (Qian Hu) is used as a bitter, acrid, slightly cold herb that disperses wind-heat, descends qi, and resolves phlegm in cough disorders.
Active Constituents
Praeruptorin A
Angular pyranocoumarin (khellactone diester)Concentration: The most abundant bioactive metabolite of the root; the marker compound on which Chinese Pharmacopoeia assay of Qian Hu rests
An orally active calcium channel blocker that produces vasodilatation and lowers blood pressure in animals. It is also a CYP3A4 substrate and is cleared rapidly by human liver microsomes through oxidation, hydrolysis, intramolecular acyl migration and glucuronidation, implying extensive hepatic first-pass elimination. Both properties matter clinically: the first for additive hypotension, the second for interaction risk.
Praeruptorin B
Angular pyranocoumarin (khellactone diester)Concentration: Second most abundant pyranocoumarin of the root after praeruptorin A
Co-occurs with praeruptorin A and shares its khellactone core. In a comparative pharmacological evaluation against whole-drug extracts it accounted, with praeruptorin A, for much of the observed activity of the crude drug. Metabolised in human and rat liver microsomes, so it contributes to the same CYP3A4 competition as praeruptorin A.
Praeruptorin C
Angular pyranocoumarin (khellactone diester)Concentration: Minor pyranocoumarin of the root; not routinely assayed
Significantly increases CYP3A4 mRNA, protein and catalytic activity through activation of the pregnane X receptor in cell models. This is an inducing rather than inhibiting action and is the mechanistic basis for expecting reduced exposure to co-prescribed CYP3A4 substrates on repeated dosing.
Praeruptorin D
Angular pyranocoumarin (khellactone diester)Concentration: Minor pyranocoumarin of the root; not routinely assayed
Up-regulates CYP3A expression via the pregnane X receptor, shown for both human CYP3A4 and rodent Cyp3a11. The authors framed the work explicitly as a prediction of herb-drug interactions between Qian Hu and co-administered CYP3A4 substrates.
Imperatorin
Linear furanocoumarinConcentration: Reported at 0.000 to 1.188 mg/g across germplasm and producing regions, the widest range of any furanocoumarin in the root
The most abundant of the root's linear furanocoumarins, and the one whose content varies most between sources. Furanocoumarins of this class are photosensitising under ultraviolet irradiation and are the structural family responsible for grapefruit-type mechanism-based inhibition of CYP3A4, which pulls in the opposite direction to the pregnane X receptor induction produced by the praeruptorins.
Bergapten (5-methoxypsoralen)
Linear furanocoumarinConcentration: Reported at 0.000 to 0.471 mg/g in Peucedanum praeruptorum root
A recognised photosensitiser used clinically in psoralen plus ultraviolet A therapy. Its presence, even at low milligram-per-gram levels, is the reason Qian Hu should not be assumed free of phototoxic potential in patients receiving phototherapy or other photosensitising drugs.
Psoralen
Linear furanocoumarinConcentration: Reported at 0.000 to 0.058 mg/g, the lowest of the three linear furanocoumarins measured
The most phototoxic of the linear furanocoumarins on a weight basis, ranked above bergapten, peucedanin and xanthotoxin in comparative phototoxicity testing, but present here at the lowest concentration of the three. Relevant to risk assessment rather than to therapeutic effect.
Oxypeucedanin
Angular-type furanocoumarinConcentration: Reported at 0.002 to 0.340 mg/g in Peucedanum praeruptorum root
Present at low and relatively consistent levels. Included because furanocoumarin content is the part of the Qian Hu profile most often overlooked when the drug is described simply as a pyranocoumarin herb.
⚠ Drug Interactions
CYP3A4 substrates with a narrow therapeutic index (ciclosporin, tacrolimus, midazolam, simvastatin, direct oral anticoagulants)
Qian Hu acts on CYP3A4 in both directions and the net effect depends on timing. Praeruptorins C and D each up-regulate CYP3A4 messenger RNA, protein and activity through pregnane X receptor activation, which on repeated dosing lowers exposure to co-administered substrates. Against that, praeruptorin A is itself a CYP3A4 substrate cleared rapidly by human liver microsomes, so acute competition for the enzyme is expected, and the root also carries the linear furanocoumarins imperatorin, bergapten and psoralen, the structural class responsible for mechanism-based CYP3A4 inhibition in grapefruit juice. The evidence is cell-based and microsomal; no human interaction study has been published, and the magnitude in patients is unknown.
Clinical note: Avoid Qian Hu in transplant patients on calcineurin inhibitors and in anyone on a CYP3A4-cleared narrow-therapeutic-index drug unless levels can be monitored. Where the herb is nonetheless used, check drug levels or clinical endpoints after roughly two weeks, and again after stopping, since induction reverses over several days.
Calcium channel blockers and other antihypertensives
Praeruptorin A, the principal constituent of the root, is characterised pharmacologically as a calcium channel blocker that mediates vasodilatation, inhibits vascular hypertrophy and reduces blood pressure in animal models of renovascular and spontaneous hypertension. Adding a herb whose main constituent shares the mechanism of a dihydropyridine is a plausible route to additive blood-pressure lowering, though no human study has measured it and dose-response in people has never been established.
Clinical note: Check blood pressure and ask about dizziness or postural symptoms in patients already on a calcium channel blocker. Not a contraindication at ordinary decoction doses, but a reason to review rather than to add blindly.
Photosensitising drugs and ultraviolet phototherapy (amiodarone, tetracyclines, thiazides, PUVA)
The root contains the linear furanocoumarins psoralen, bergapten and imperatorin, which are photosensitising, phototoxic, mutagenic and photocarcinogenic under irradiation, with phototoxic potency ranking psoralen above bergapten above peucedanin above xanthotoxin. Concentrations in Qian Hu are low, in the range of hundredths to about one milligram per gram, and no phototoxic reaction has been reported from the drug in clinical use, so this is a mechanism-based caution rather than a documented event.
Clinical note: Ask about phototherapy and photosensitising medication, and advise sun protection during courses in patients on such drugs. Do not co-prescribe during an active PUVA course.
Zi Hua Qian Hu (Angelica decursiva, formerly Peucedanum decursivum) supplied as Qian Hu
Angelica decursiva root was listed as a co-source of Qian Hu in Chinese Pharmacopoeia editions from 1963 to 2000 and was separated out from the 2005 edition, since when only Peucedanum praeruptorum may be dispensed as Qian Hu. The two are chemically distinct: P. praeruptorum is defined by angular pyranocoumarins (praeruptorins A and B), whereas A. decursiva contains mainly linear dihydropyranocoumarins and linear dihydrofuranocoumarins. Because market demand outstrips supply and the roots look similar, P. praeruptorum is also adulterated by a wider set of regional substitutes; DNA barcoding of the nuclear ribosomal internal transcribed spacer region has been used to separate the genuine drug from 13 substitutes and 23 adulterants, and hand-held near-infrared spectroscopy with partial least squares discriminant analysis reached 93.4 percent accuracy against adulterants.
Clinical note: Buy Qian Hu only from suppliers who can state the binomial and, ideally, provide identity testing. A pale root with a whitish cross-section and indistinct radial markings should prompt a query. Substituted A. decursiva will not deliver the praeruptorin content the prescription assumes.
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、辛，微寒。归肺经。 — Chinese Pharmacopoeia 2020, quoted verbatim; route and cautions preserved. Replaces a cleared category-filler value. |
Dui Yao — Herb Pairs
The classical two-herb combinations this herb appears in, each with an action neither herb has alone.
One disperses wind-heat and descends qi, the other descends qi and dispels phlegm; together they stop cough with copious phlegm whether or not an exterior pattern remains.
Named pairing — Lü Jingshan, Shi Jinmo Dui Yao
Evidence Tier
Strong evidence · 5 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
1
1 verified · 0 unverified
Randomized controlled trial
0
Other clinical trial
0
Observational / case report
0
In vitro / animal
4
1 verified · 3 unverified
Show 4 studies
- Up-regulatation of CYP3A expression through pregnent X receptor by praeruptorin D isolated from Peucedanum praeruptorum Dunn
- PXR-Mediated Upregulation of CYP3A Expression by Herb Compound Praeruptorin C from Peucedanum praeruptorum Dunn
- Identification of cytochrome P450 isoenzymes involved in metabolism of (+)-praeruptorin A, a calcium channel blocker, by human liver microsomes using ultra high-performance liquid chromatography coupled with tandem mass spectrometry
- Isolation of praeruptorins A and B from Peucedanum praeruptorum Dunn. and their general pharmacological evaluation in comparison with extracts of the drug
Other / unclassified
0
Verified: design read from PubMed for a DOI that resolves to the cited paper Unverified: taken from the study's recorded description
Clinical Studies
Up-regulatation of CYP3A expression through pregnent X receptor by praeruptorin D isolated from Peucedanum praeruptorum Dunn
Praeruptorin D activated the pregnane X receptor and up-regulated CYP3A4 in human cell models and Cyp3a11 in rodent systems. The authors state the purpose explicitly as predicting herb-drug interactions between praeruptorin D, Qianhu and co-administered CYP3A4 substrates. Cell and animal level; the title is registered with the two typographical errors shown and is reproduced as published. An erratum appeared in the same journal in 2014; the article has not been retracted or subjected to an expression of concern.
PXR-Mediated Upregulation of CYP3A Expression by Herb Compound Praeruptorin C from Peucedanum praeruptorum Dunn
Praeruptorin C significantly increased CYP3A4 messenger RNA, protein expression and functional activity through a pregnane X receptor mediated pathway. Confirms that the induction signal in this herb is not carried by a single coumarin. An erratum was published in the same journal in 2014; the article has not been retracted or subjected to an expression of concern.
Identification of cytochrome P450 isoenzymes involved in metabolism of (+)-praeruptorin A, a calcium channel blocker, by human liver microsomes using ultra high-performance liquid chromatography coupled with tandem mass spectrometry
Human liver microsome study identifying the cytochrome P450 isoenzymes that metabolise praeruptorin A and confirming CYP3A4 as a route of clearance. Praeruptorin A was metabolised rapidly, indicating extensive hepatic first-pass elimination, with oxidation, hydrolysis, intramolecular acyl migration and glucuronidation as the main routes. Human tissue but not human dosing.
Isolation of praeruptorins A and B from Peucedanum praeruptorum Dunn. and their general pharmacological evaluation in comparison with extracts of the drug
Compared isolated praeruptorins A and B with whole extracts of the root in a general pharmacological screen, tying the activity of the crude drug to its two principal pyranocoumarins. Useful because it tests the isolated compounds against the drug as dispensed rather than only in isolation.
Biological Activities and Pharmacokinetics of Praeruptorins from Peucedanum Species: A Systematic Review
Systematic review of the praeruptorin literature across Peucedanum species covering pharmacology and pharmacokinetics. Its central caution is that despite long traditional use, clinical trials establishing dose-response, efficacy and safety in humans are lacking, which remains the accurate summary of Qian Hu's evidence base.
Historical Texts
Ming Yi Bie Lu
Six Dynasties, c. 500 CE, attributed to Tao HongjingBen Cao Gang Mu (Li Shizhen)
Ming dynasty, 1596Zhi Wu Ming Shi Tu Kao (Wu Qijun)
Qing dynasty, 1848Pharmacopoeia of the People's Republic of China
Modern regulatory, 1963 to 2000 editions and 2005 edition onwardReferences
- Wang Q, Sun Q, Huang Q, Qin L, Zhu B. The traditional uses, pharmacology, and phytochemistry of Peucedanum praeruptorum Dunn . Frontiers in Pharmacology (2024) [DOI]
- Chen R, Wang W, Chen C, Xu Z, Pu J, Xu P. Quality formation in Peucedanum praeruptorum dunn: metabolite biosynthesis, geoherbal variation, and early bolting regulation . Frontiers in Plant Science (2026) [DOI]
- Liu Z, Zhou J, Wang W, Liu M. Molecular authentication of the traditional medicinal plant Peucedanum praeruptorum and its substitutes and adulterants by dna 0 - barcoding technique . Pharmacognosy Magazine (2014) [DOI]
- Wang F, Jia B, Song X, Dai J, Li X, Gao H, Pan H, Yan H, Han B. Rapid Identification of Peucedanum praeruptorum Dunn and Its Adulterants by Hand-Held Near-Infrared Spectroscopy . Journal of AOAC INTERNATIONAL (2021) [DOI]
- Kim JH, Doh EJ, Lee G. Chemotaxonomic Classification of Peucedanum japonicum and Its Chemical Correlation with Peucedanum praeruptorum, Angelica decursiva, and Saposhnikovia divaricata by Liquid Chromatography Combined with Chemometrics . Molecules (2022) [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.
📝 Notes
Public notes from the community and your own private notes on Qian Hu.
No notes yet.