Hu Zhang (Reynoutria japonica): Benefits, Dosage, Safety & Evidence

Questions fréquentes

How does Hu Zhang work in the body?

Hu Zhang contains resveratrol and emodin as its primary active compounds. Resveratrol acts as a potent antioxidant and modulates inflammatory pathways by inhibiting NF-kappaB signaling. Emodin provides laxative effects through intestinal stimulation and demonstrates anti-inflammatory properties. The anthraquinones in Hu Zhang may also inhibit tumor cell proliferation. In Traditional Chinese Medicine, Hu Zhang 'invigorates blood' and clears damp-heat, explaining its traditional use for blood stasis and joint conditions. Evidence level: C.

Can I take Hu Zhang with blood thinners or anticoagulants?

No, Hu Zhang should not be combined with anticoagulant or antiplatelet medications. The herb contains compounds that affect blood clotting and may increase bleeding risk. Taking Hu Zhang alongside warfarin, aspirin, clopidogrel, or similar drugs can potentiate their effects, potentially causing excessive bleeding, bruising, or prolonged bleeding times. Patients on blood thinners should avoid Hu Zhang entirely and consult a healthcare provider before considering any herbal supplementation. Evidence level: C.

What is the recommended dosage for Hu Zhang root?

Traditional decoction dosage ranges from 9-15 grams of dried Hu Zhang root daily. For standardized resveratrol extracts derived from Hu Zhang, typical adult dosages range from 500mg to 2 grams daily. Dosage should be individualized based on the condition being addressed and personal tolerance. Starting with lower doses helps minimize gastrointestinal side effects like nausea or diarrhea. Always consult a qualified healthcare practitioner for personalized dosing guidance. Evidence level: Traditional.

Is Hu Zhang safe during pregnancy and breastfeeding?

Hu Zhang is considered unsafe during pregnancy and should be strictly avoided. The herb contains anthraquinones, including emodin, which can stimulate uterine contractions and potentially cause miscarriage. Additionally, Hu Zhang exhibits estrogen-like effects that could disrupt hormonal balance during pregnancy. There is insufficient safety data for breastfeeding, so avoidance is recommended. Women who are pregnant, planning pregnancy, or breastfeeding should not use Hu Zhang in any form. Evidence level: C.

What are the side effects of Hu Zhang (Japanese knotweed)?

Common side effects of Hu Zhang include nausea, diarrhea, and abdominal discomfort, primarily due to its anthraquinone content. The herb may increase bleeding risk, especially in susceptible individuals. Because Hu Zhang contains compounds with estrogen-like activity, it may cause hormonal side effects in some users. Those with hormone-sensitive conditions, bleeding disorders, or taking anticoagulants should avoid Hu Zhang. Discontinue use if adverse reactions occur and consult a healthcare provider. Evidence level: C.

Fiche d'information compilée à partir de PubMed

Cette fiche a été compilée à partir de résumés PubMed (NIH) avec l'assistance d'une IA. Chaque affirmation factuelle est citée par un article PubMed réel (voir la liste des sources). Elle n'a pas encore été révisée par un humain — confirmez auprès d'un professionnel de santé avant utilisation.

Compilé à partir de 30 articles PubMed · modèle : gemma4:31b

Résumé

Hu Zhang (Reynoutria japonica), also known as Japanese knotweed, is a traditional Chinese medicinal herb used for inflammatory diseases, infections, and respiratory disorders [PMID:41046083, PMID:35770098].

Contexte

Reynoutria japonica Houtt. (synonym Fallopia japonica) is a perennial herbaceous plant native to East Asia and is recognized as one of the world's most destructive invasive species [PMID:35009007, PMID:39993002]. It is a mixed auto-/allooctoploid plant characterized by aggressive growth and strong adaptability [PMID:39993002].

Usages traditionnels

In traditional Chinese medicine, it is used to invigorate blood, cool heat, resolve toxicity, clear heat in the body, improve blood and qi circulation, eliminate phlegm, and relieve cough [PMID:35770098, PMID:35281919]. It has been traditionally used to treat favus, jaundice, scald, constipation, and liver cancer [PMID:35770098, PMID:40524029].

Composés actifs

The plant contains stilbenes (notably resveratrol and polydatin), anthraquinones (including emodin and emodin-6-O-β-D-glucoside), flavonoids (such as luteolin), and proanthocyanidins/flavan-3-ols (including (-)-epicatechin and procyanidin B2) [PMID:35770098, PMID:34961091, PMID:24114447, PMID:33672472, PMID:31963589].

Mécanisme d'action

Resveratrol inhibits the activation of NLRP3 inflammasomes by promoting mitophagy [PMID:34335041]. Luteolin targets AKT1 to inhibit macrophage apoptosis and mitochondrial damage in the context of acute lung injury [PMID:41046083]. Emodin-6-O-β-D-glucoside attenuates high-glucose-induced vascular inflammation by reducing vascular permeability, monocyte adhesion, ROS formation, and NF-κB activation [PMID:24114447].

Preuves cliniques

Preuve DGouty Arthritis

Resveratrol from R. japonica significantly improves gait score and synovitis in rat models and inhibits MSU-induced peritoneal inflammation [PMID:34335041]

Preuve AAcute Respiratory Tract Infections

A systematic review was conducted to evaluate the effect of R. japonica as a single herb or in formulas for RTIs [PMID:35281919]

Preuve DAcute Lung Injury

Luteolin from R. japonica protects against acute lung injury by inhibiting macrophage apoptosis and mitochondrial damage via AKT1 [PMID:41046083]

Preuve DSARS-CoV-2

A 70% ethanolic extract of the rhizome bark showed a statistically significant antiviral effect against wild-type SARS-CoV-2 in vitro [PMID:36134975]

Preuve CHyperuricemia

R. japonica is identified as a single medicine effective for lowering uric acid [PMID:37193181]

Sécurité et effets indésirables

Hu Zhang has been listed among herbal traditional Chinese medicine products associated with potential hepatotoxicity [PMID:26357619].

Synthèse des preuves

The evidence consists primarily of in vitro studies, animal models (Level D), and systematic reviews of existing trials (Level A), with some general pharmacological reviews (Level C). Most findings are preclinical.

Sources PubMed

1.PMID: 34335041 (2021) — Resveratrol Relieves Gouty Arthritis by Promoting Mitophagy to Inhibit Activation of NLRP3 Inflammasomes. · Journal of inflammation research
2.PMID: 35281919 (2022) — Reynoutria japonica Houtt for Acute Respiratory Tract Infections in Adults and Children: A Systematic Review. · Frontiers in pharmacology
3.PMID: 35009007 (2021) — Allelopathy of Knotweeds as Invasive Plants. · Plants (Basel, Switzerland)
4.PMID: 34961091 (2021) — New Approaches on Japanese Knotweed (Fallopia japonica) Bioactive Compounds and Their Potential of Pharmacological and Beekeeping Activities: Challenges and Future Directions. · Plants (Basel, Switzerland)
5.PMID: 39993002 (2025) — The mixed auto-/allooctoploid genome of Japanese knotweed (Reynoutria japonica) provides insights into its polyploid origin and invasiveness.

Hu Zhang

Sources et citations

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