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PubMed · Persicaria hydropiper (L.) Delarbre: A review on traditional uses, bioactive chemical constituents and pharmacological and toxicological activities. (2020)
PubMed · Polygonum hydropiper L. ethanol extract attenuates ferroptosis and ulcerative colitis by modulating glutathione metabolism through inhibition of KEAP1-Nrf2 interaction. (2025)
Reviewed by: HerbAlly Editorial Team, Medical herbalists and healthcare professionals
Last updated: April 2026
Calculate a safe dose of Persicaria Hydropiper Herb
Persicaria hydropiper contains polygodial as its primary active compound, which provides antifungal and anti-inflammatory effects. The herb's tannins create astringent actions that explain its traditional use as a hemostatic agent for bleeding conditions and hemorrhoid treatment. These astringent properties help tighten and soothe inflamed tissues. The plant also functions as an emmenagogue, stimulating uterine contractions and menstrual flow. Evidence level: C (limited clinical evidence).
Does Persicaria hydropiper interact with medications?
Limited research exists on specific drug interactions for Persicaria hydropiper. Due to its hemostatic properties, it may theoretically interact with anticoagulant or antiplatelet medications such as warfarin or aspirin. The herb's effects on kidney function could potentially interact with diuretics or medications metabolized through the kidneys. Patients taking blood thinners, kidney medications, or hormone therapies should consult a healthcare provider before use. Evidence level: C.
What is the recommended dosage for Persicaria hydropiper?
Traditional adult dosages for Persicaria hydropiper include 2-4 grams of dried herb prepared as a tea, or 3-4 milliliters of tincture daily. These recommendations derive from folk medicine traditions rather than clinical trials. Due to potential kidney irritation and burning sensations, users should start with lower doses and avoid prolonged use. Individuals with kidney conditions should avoid this herb entirely. Evidence level: C (traditional use).
Is Persicaria hydropiper safe during pregnancy?
Persicaria hydropiper is contraindicated during pregnancy and should be strictly avoided. The herb acts as an emmenagogue, stimulating uterine contractions and menstrual flow, which poses significant risk of miscarriage or pregnancy complications. Traditional medicine systems have historically used this plant to induce menstruation. Pregnant women, those attempting to conceive, and breastfeeding mothers should not use this herb. Evidence level: C (traditional contraindication).
What are the side effects of Persicaria hydropiper?
Reported side effects of Persicaria hydropiper include kidney irritation and burning sensations, particularly with higher doses or extended use. The herb's pungent compounds, including polygodial, can cause mucous membrane irritation. Individuals with pre-existing kidney disease should avoid this herb due to its nephrotoxic potential. Discontinue use immediately if experiencing urinary discomfort, burning sensations, or other unusual symptoms. Evidence level: C.
What is Persicaria hydropiper used for in herbal medicine?
Persicaria hydropiper, also known as water pepper or smartweed, has been used in European and Asian folk medicine primarily for treating hemorrhoids, regulating menstrual cycles, and addressing digestive complaints. Its astringent tannins make it useful as a hemostatic agent for minor bleeding. Laboratory studies demonstrate antifungal properties. Traditional applications include both internal preparations and external applications for hemorrhoids. Evidence level: C (limited clinical evidence).
PubMed-compiled information sheet
This sheet was compiled from PubMed (NIH) abstracts using AI assistance. Every factual claim is cited to a real PubMed article (see the source list). It has not yet been human-reviewed — confirm with a healthcare provider before use.
Compiled from 30 PubMed articles · model: gemma4:31b
Summary
Persicaria hydropiper, also known as water pepper or smartweed, is a globally distributed medicinal herb used traditionally for various ailments and as a culinary spice [PMID:31884037, PMID:33655861, PMID:41940699].
Background
Persicaria hydropiper (L.) Delarbre (synonym Polygonum hydropiper L.) is an annual herb from the Polygonaceae family found in temperate zones and tropical northern hemispheres, including Asia, Europe, China, Bangladesh, India, and Japan [PMID:31884037, PMID:33655861, PMID:41940699, PMID:24834098].
Traditional uses
Traditional uses include treatment of respiratory disorders, edema, snake bites, gynecological disorders, ulcers, anxiety, pain, cancer, hemorrhoids, antifertility, diarrhea, and dyspepsia [PMID:31884037, PMID:35259273, PMID:33655861]. In China, decoctions are used for dysentery and gastroenteritis [PMID:37952732], and Mishing women in Assam, India, use dry root powder for birth control [PMID:36465841]. It is also used as an astringent, sedative, and antiseptic [PMID:31884037].
Active compounds
The plant contains flavonoids (including isoquercitrin, isorhamnetin, quercetin, and kaempferol-3-p-coumaroyl), drimane-type sesquiterpenoids (notably polygodial, drimenol, euryfuran, and isodrimeninol), phenylpropanoids, alkaloids, carbohydrates, anthraquinones, steroids, coumarin, and simple phenolics [PMID:31884037, PMID:35259273, PMID:41940699, PMID:33655861, PMID:16608232, PMID:24834098, PMID:30208642, PMID:21413092].
Mechanism of action
Polygodial induces oxidative stress to activate apoptotic signaling in castration-resistant prostate cancer cells [PMID:36358679]. Isoquercitrin and isorhamnetin activate the Wnt/β-catenin pathway to inhibit adipocyte differentiation in 3T3-L1 cells [PMID:21413092]. A neutral polysaccharide from the herb modulates AKT/PI3K/mTOR and MAPK signaling pathways to ameliorate intestinal barrier injury [PMID:37952732].
Methanol extract of leaves showed dose-dependent in vitro cestocidal activity, causing parasite mortality and impairment of the scolex [PMID:36910324]
Evidence DCastration-Resistant Prostate Cancer
Polygodial inhibits cell viability, colony formation, and migration, and induces G0 phase cell cycle arrest in vitro [PMID:36358679]
Evidence DType 2 Diabetes (Enzymatic targets)
Extracts and essential oils exhibit inhibitory effects on α-amylase and α-glucosidase activities in vitro [PMID:32640649, PMID:35086537, PMID:35096118, PMID:35463090]
Evidence DObesity (Adipogenesis)
Extracts and specific flavonoids (isoquercitrin, isorhamnetin) inhibit the differentiation of 3T3-L1 adipocytes [PMID:21413092]
Evidence DIntestinal Barrier Injury (LPS-induced)
A neutral polysaccharide (PHP) ameliorates injury in mice by regulating gut microbiota [PMID:37952732]
Evidence D
Safety & adverse effects
Review data mentions toxicological aspects and mutagenicity, but specific adverse effects are not detailed in the provided abstracts [PMID:31884037, PMID:24834098]. Polygodial was reported as non-toxic to primary human hepatocytes [PMID:36358679].
Evidence summary
The current evidence is primarily based on in vitro studies, animal models, and literature reviews (Level C and D). There are no human clinical trials (RCTs) or meta-analyses provided in the source text.
PubMed sources
1.PMID: 31884037 (2020) — Persicaria hydropiper (L.) Delarbre: A review on traditional uses, bioactive chemical constituents and pharmacological and toxicological activities. · Journal of ethnopharmacology
2.PMID: 35259273 (2022) — A review on the ethnopharmacology, phytochemistry and pharmacology of Polygonum hydropiper Linn. · The Journal of pharmacy and pharmacology
3.PMID: 41940699 (2026) — Drimane Sesquiterpene-Rich Volatile Oil Profile of Water Pepper (Persicaria hydropiper), a Widely Distributed Spicy Herb. · Journal of food science
4.PMID: 33655861 (2021) — Review on Pharmacological and Phytochemical Prospects of Traditional Medicinal Plant: Persicaria hydropiper (Smartweed). · Current topics in medicinal chemistry
5.PMID: 16608232 (2006) — Comparison of volatile constituents of Persicaria odorata(Lour.) Soják (Polygonum odoratum Lour.) and Persicaria hydropiper L. Spach (Polygonum hydropiper L.).
Government sources
No direct government monograph is available for this herb. The content below is AI-generated and has not been verified against an authoritative government source. Use the search links to check official sources before relying on this information.
6.PMID: 24834098 (2014) — Ethnobotanical, Phytochemical, Pharmacological, and Toxicological Aspects of Persicaria hydropiper (L.) Delarbre. · Evidence-based complementary and alternative medicine : eCAM
7.PMID: 36910324 (2023) — In vitro cestocidal activity of Persicaria hydropiper (L.) Delarbre, a traditionally used anthelmintic plant in India. · Journal of parasitic diseases : official organ of the Indian Society for Parasitology
8.PMID: 37952732 (2024) — A neutral polysaccharide from Persicaria hydropiper (L.) Spach ameliorates lipopolysaccharide-induced intestinal barrier injury via regulating the gut microbiota and modulating AKT/PI3K/mTOR and MAPK signaling pathways. · Journal of ethnopharmacology
9.PMID: 32640649 (2020) — Evaluation of Alpha-Amylase Inhibitory, Antioxidant, and Antimicrobial Potential and Phytochemical Contents of Polygonum hydropiper L. · Plants (Basel, Switzerland)
10.PMID: 30208642 (2018) — Identification of Antiglycative Compounds in Japanese Red Water Pepper (Red Leaf Variant of the Persicaria hydropiper Sprout). · Molecules (Basel, Switzerland)
11.PMID: 36465841 (2022) — Fertility regulatory potential of Persicaria hydropiper (L.) Delarbre methanolic root extract in female albino mice: An insight into the phytochemicals present and role of the extract in contraception. · Saudi pharmaceutical journal : SPJ : the official publication of the Saudi Pharmaceutical Society
12.PMID: 21413092 (2011) — Persicaria hydropiper (L.) spach and its flavonoid components, isoquercitrin and isorhamnetin, activate the Wnt/β-catenin pathway and inhibit adipocyte differentiation of 3T3-L1 cells. · Phytotherapy research : PTR
13.PMID: 35086537 (2022) — HPLC-DAD phenolics analysis, α-glucosidase, α-amylase inhibitory, molecular docking and nutritional profiles of Persicaria hydropiper L. · BMC complementary medicine and therapies
14.PMID: 36358679 (2022) — Polygodial, a Sesquiterpene Dialdehyde, Activates Apoptotic Signaling in Castration-Resistant Prostate Cancer Cell Lines by Inducing Oxidative Stress. · Cancers
15.PMID: 35096118 (2022) — Phytochemical Analysis, α-Glucosidase and Amylase Inhibitory, and Molecular Docking Studies on Persicaria hydropiper L. Leaves Essential Oils. · Evidence-based complementary and alternative medicine : eCAM
16.PMID: 29572068 (2018) — Polygodial analog induces apoptosis in LNCaP prostate cancer cells. · European journal of pharmacology
17.PMID: 35463090 (2022) — Antioxidant, Enzyme Inhibitory, and Molecular Docking Approaches to the Antidiabetic Potentials of Bioactive Compounds from Persicaria hydropiper L. · Evidence-based complementary and alternative medicine : eCAM