Japanese sophora

Other Names

Acacia del JapónAnagyris chinensisAnagyris foetidaAnagyris sinensisArbre des pagodes du JaponChinese necklacepodChinese scholar treeEndsinFlos Immaturus Sophorae JaponicaeFlos SophoraeFlos Sophorae ImmaturusFructus SophoraeGuo huaiHoeHoe-wha-na-mooHuaiHuai huaHuai hua miHuai jiaoHuai miHuai shuHuaihuaHuaimiJapanese pagoda treeJapanese pagodatreeJapanischer SchnurbaumMacrotropis foetidaOrmosia esquiroliiPagoda treePongamia chinensisRadiusia chinensisRobinia mitisSari cinaSchnurbaumScholar treeSofora del GiapponeSofora YaponskayaSophora japonicaSophora japonica f. oligophyllaSophora japonica L.Sophora japonica var. korolkowiiSophora japonica var. pendulaSophora japonica var. pubescensSophora japonica var. vestitaSophora japonica var. violaceaSophora korolkowiiSophora maireiSophora pendulaSophora pubescensSophora vaniotiiSophora violaceaSophore du JaponStifnolobium YaponskiStyphnolobium japonicumStyphnolobium japonicum (L.) SchottStyphnolobium japonicum f. oligophyllumStyphnolobium japonicum f. violaceumStyphnolobium japonicum var. pendulumStyphnolobium japonicum var. pubescensTbwai huaUmbrella treeWai-faWei-hwaZhong guo huai

Synopsis

Japanese Sophora (Sophora japonica / Styphnolobium japonicum): A Comprehensive Reference

1. Identity and Botanical Classification

1.1 Nomenclature

The plant known commercially as Japanese sophora is Styphnolobium japonicum, the Japanese pagoda tree (also known as the Chinese scholar tree and pagoda tree), a species of deciduous tree in the subfamily Faboideae of the pea family Fabaceae, formerly included within a broader interpretation of the genus Sophora. The name Styphnolobium japonicum is now generally accepted as the correct botanical name, however in commerce, the older name Sophora japonica is often used. The nomenclature change is based on chromosome numbers as well as morphological and cytological differences.

The species of Styphnolobium differ from Sophora in lacking the ability to form symbioses with rhizobia (nitrogen-fixing bacteria) on their roots. In herbal medicine literature, pharmacopoeial monographs, and the supplement industry, the older name Sophora japonica L. remains in widespread use and is retained throughout this article for consistency with primary sources.

1.2 Common Names

The species is variously known as Chinese scholar tree (Chinese: 槐, "zhong guo huai," or "huai shu"), Japanese pagoda tree (in English), Hoe-wha-na-moo (in Korean), Sophora du Japon (in French), Japanischer Schnurbaum (in German), and acacia del Japón (in Spanish). In Japanese, it is called 槐 (enju), and the flowers are known as 槐の花 (enju no hana). In Traditional Chinese Medicine (TCM), the dried flower is known as Huai Hua or Flos Sophorae, and the dried flower bud as Huai Mi or Flos Sophorae Immaturus; the dried fruit is known as Huai Jiao or Fructus Sophorae.

1.3 Botanical Description and Natural Distribution

Sophora japonica is a deciduous, small to medium-sized tree up to 15–30 m tall; bole generally short; bark surface corrugated, dark greenish-brown or dark grey-green and spreading branches, with paler lenticels; crown broad. The leaves are alternate, pinnate, with nine to 21 leaflets, and the flowers in pendulous racemes similar to those of the black locust.

It is a medium-sized deciduous tree commonly found in China, Japan, Korea, Vietnam, and other countries. Styphnolobium japonicum is native to China. It has been widely introduced as an ornamental and shade tree across temperate regions of Europe, North America, and beyond.

1.4 Plant Parts Used Medicinally

Each and every part of this plant, including the flowers, buds, leaves, bark, fruits, seeds, pericarp, stems, and roots, is used as medicine, particularly in China, Japan, Korea, and Asia. However, the dry flowers (Huaihua or Flos Sophorae) and the flower buds (Huaimi or Flos Sophorae Immaturus) are included in both the Chinese Pharmacopoeia and the European Pharmacopoeia.

1.5 Pharmacopoeial Status

The use of this plant has been recorded in classical medicinal treatises of ancient China, and it is currently recorded in both the Chinese Pharmacopoeia and European Pharmacopoeia. The flowers and flower buds are included in the Chinese and European pharmacopoeias, in which they are referred to as Flos Sophorae (FS) and Flos Sophorae Immaturus (FSI), respectively. In the Chinese Pharmacopoeia, FS and FSI have been recorded to exhibit a bitter taste and a slightly cold nature, possessing hemostatic properties and the ability to clear liver heat.

The dried flower and flower bud of Styphnolobium japonicum (L.) Schott (Japanese Sophora flower and Japanese Sophora flower bud, respectively) have long been used as herbal medicines in Asia. Today, they are marketed as dietary supplements in the United States for their anti-oxidative properties and as a source of flavonoids, including rutin and quercetin.

1.6 Commercial Forms and Preparations

When "Sophora japonica extract" appears on a supplement label, it can mean several things: a crude bud or flower extract standardised to a certain percentage of total flavonoids, or a highly purified rutin concentrate (often 95% rutin) that happens to be derived from Sophora japonica. Unlike many other plant sources of rutin, Sophora japonica buds can naturally contain up to 20% rutin by dry weight, making it the most efficient, cost-effective commercial source of this compound on the global market.

Preparations available include standardized capsules or tablets (commonly standardized to 95–98% rutin, or to ≥90% total flavonoids), crude dried flower bud powder for decoction (traditional), quercetin-rich extracts, topical formulations for vascular or skin applications, and combination herbal formulas in TCM practice.

2. Traditional and Historical Use

2.1 Chinese Medicine — Origins and Classical Texts

Sophora japonica extract has a rich history in traditional Eastern medicine, particularly in Chinese medicine where it has been documented for over 2,000 years. Known as "Huai Hua" or "Huai Mi," this extract was first mentioned in the ancient Chinese pharmacopeia Shennong Ben Cao Jing.

Styphnolobium japonicum (formerly Sophora japonica) is one of the 50 fundamental herbs used in traditional Chinese medicine. Flos Sophorae Immaturus and Fructus Sophorae, used in TCM, are the dried flower buds and ripe fruits of the leguminous plant S. japonica. They are known to eliminate "heat" and purge "fire", cool the blood, and stop bleeding, and they have been used to treat a variety of diseases in ancient China.

2.2 Core Traditional Indications

The flower buds and fruits of S. japonica, also known as Flos Sophorae Immaturus and Fructus Sophorae in China, are most commonly used in Asia (especially in China) to treat hemorrhoids, hematochezia, hematuria, hematemesis, hemorrhinia, uterine or intestinal hemorrhage, arteriosclerosis, headache, hypertension, dysentery, dizziness, and pyoderma.

Traditional practitioners utilized the extract primarily for its hemostatic properties to control bleeding, especially for hemorrhoids, uterine bleeding, and hematemesis. Its cooling nature made it valuable for treating conditions characterized by "heat" in traditional Chinese medicine. Beyond hemostasis, it was used for reducing fever, clearing heat toxins, and alleviating inflammatory conditions.

2.3 Japanese and Korean Traditional Use

Japanese and Korean traditional medicine systems incorporated it into formulations for eye conditions, including redness and excessive tearing. Traditionally, S. japonicum L. has been documented in East Asian pharmacopoeias as "Huai Jiao" or "Huai Shi," described as having cold properties with bitter and astringent tastes.

2.4 Cultural Significance

It also symbolized nobility, honor, and sacrifice in Chinese culture. Scholar trees were traditionally planted around schools, temples, and houses in China. The herb has appeared in classical Chinese texts for over a thousand years and is often included in formulas for lower-body heat and dampness, such as Huai Jiao Wan.

2.5 Preparation Methods in Traditional Use

In TCM, the dried flower bud and fruit were administered orally as decoctions, typically prepared by boiling in water. S. japonica has long been used in traditional Chinese medicine (TCM) due to its wide range of biological activities, and is administered orally. Sophora japonica is a commonly used Chinese medicine. It is a dried flower bud of the leguminous plant Huai, tastes bitter and slightly cold, and has the effects of cooling blood to stop bleeding, clearing liver and reducing fire.

3. Phytochemistry: Key Constituents and Active Compounds

3.1 Overall Chemical Profile

Approximately 153 chemical compounds, including flavonoids, isoflavonoids, triterpenes, alkaloids, polysaccharides, amino acids, and other compounds, have been isolated from the leaves, branches, flowers, buds, pericarps, and/or fruits of S. japonica.

3.2 Flavonoids and Isoflavonoids (Primary Class)

Among these secondary metabolites, flavonoids and isoflavonoids are considered the most important. Rutin, a citrus flavonoid glycoside, is the most important and abundant component of S. japonica.

Rutin was the most dominant flavonoid in Sophora japonica flowers (SJF) with a content range of 72.31–88.15 mg/g, followed by quercetin (13.05–20.30 mg/g).

The main aglycon moieties found in SJF were quercetin, kaempferol, and isorhamnetin. Additional flavonoids present in the plant are kaempferol, quercetin, and their derivatives, such as kaempferol 3-O-β-rutinoside and tamarixetin.

The seeds and fruit are particularly rich in isoflavonoids. Compounds isolated from the seeds include genistin, sophoricoside, sophorabioside, sophoraflavonoloside, genistein 7,4′-di-O-β-D-glucopyransoide, kaempferol 3-O-α–L-rhamnopyranosyl(1→6)β-D-glucopyranosyl(1→2)β-D-glucopyranoside, and rutin.

An isoflavone called sophoricoside (genistein-4′-β-D-glucoside) was extracted from S. japonica. It exhibits many pharmacological properties, including estrogenic activity, anti-inflammatory, antioxidant, anti-diabetic, and immunomodulatory effects.

Active constituents include rutin (a flavonoid), quercetin, sophoricoside (an isoflavone glycoside), alkaloids, and polysaccharides, which give the plant its anti-inflammatory, antioxidant, vascular-protective, and hemostatic effects.

3.3 Rutin: Chemistry and Key Properties

Rutin, a 3′,4′,5,7-tetrahydroxyflavone-3β-doside also known as vitamin P, is a bioflavonoid that generally exhibits cardioprotective, anti-inflammatory, anticancer, antibacterial, and antioxidant activities. Chemically, rutin is a glycoside of quercetin combined with the disaccharide rutinose. When rutin is consumed in foods or supplements, the bacteria in the gut convert it into quercetin, another chemical naturally found in plants.

3.4 Alkaloids

Some key alkaloid constituents include matrine, sophocarpine, oxymatrine, and sophoranol. Triterpenes, phospholipids, alkaloids, amino acids, and fatty acids have been reported as the main chemical constituents of the seeds of this plant. These alkaloids are more prominently associated with other Sophora species (e.g., S. flavescens) and are present at lower levels in S. japonica compared to the predominant flavonoids.

3.5 Polysaccharides and Other Compounds

The plant is enchanted with steroids, phospholipids, flavonoids, isoflavonoids, alkaloids, triterpenes, and other phenolic compounds. Polysaccharides found in the plant have been associated with immunomodulatory properties in preclinical settings.

4. Mechanisms of Action

4.1 Vascular and Hemostatic Mechanisms

The modern pharmacological literature has confirmed that rutin and quercetin have specific abilities to enhance the resistance of capillaries and exert systemic hemostatic effects, as well as powerful anti-inflammatory, antioxidant, anti-diabetes, and anti-hyperuricemia effects.

Sophora japonica extract exerts protective effects on the vascular system through several biological mechanisms. The rutin and quercetin components inhibit the enzyme hyaluronidase, which breaks down proteoglycans and hyaluronic acid in vascular walls. Studies show that rutin improves endothelial function by increasing the production of nitric oxide, a natural vasodilator, in human endothelial cells. This helps regulate blood pressure and reduces vascular inflammation, making it relevant in the treatment of chronic venous disorders such as varicose veins and venous insufficiency.

Rutin improves blood circulation by thinning blood, inhibiting platelet aggregation, and decreasing capillary permeability. Rutin's most celebrated property is its ability to strengthen capillary walls and reduce their permeability and fragility. This is achieved by inhibiting the breakdown of collagen in the blood vessel walls and by providing antioxidant protection against damage.

4.2 Anti-Inflammatory Mechanisms

The anti-inflammatory action of quercetin and other flavonoids in the extract complements rutin's vascular effects. By inhibiting pro-inflammatory enzymes and cytokines, the extract helps reduce the fluid leakage and inflammatory response associated with venous insufficiency and injury, further aiding in the reduction of edema.

4.3 Phytoestrogenic / Bone-Related Mechanisms

Upon ingestion, sophoricoside is metabolized by gut microbiota into genistein, an aglycone with significantly enhanced bioactivity and bioavailability. This biotransformation, facilitated by intestinal microbes producing β-glucosidase, is crucial for its therapeutic efficacy.

Genistein inhibited osteoclast and stimulated osteoblast function, mainly through the osteoprotegerin-sRANKL system. Both sophoricoside-rich and aglycone-rich extracts significantly reduced weight gain and alleviated vaginal dryness, with Rex demonstrating superior thermoregulatory stabilization. Histological and molecular analyses revealed preserved trabecular bone integrity through the downregulation of RANKL and upregulation of TGF-β.

4.4 Antioxidant Mechanisms

Oxidative stress, caused by an imbalance between free radicals and the body's antioxidant defenses, is a fundamental driver of aging and chronic disease. The flavonoids in Sophora japonica extract, particularly rutin and quercetin, are exceptional free radical scavengers. By neutralizing reactive oxygen species (ROS), the extract helps protect cells throughout the body from oxidative damage to DNA, proteins, and lipids.

5. Scientific Evidence by Area of Use

5.1 Vascular Health, Chronic Venous Insufficiency, and Capillary Fragility

This is the most thoroughly investigated therapeutic area for Sophora japonica and its principal constituent, rutin.

According to a recent Cochrane review, rutin, classified as a phlebotonic, has primarily been studied for its effects in the treatment of chronic venous insufficiency (CVI). It acts by slightly reducing edema of the lower limbs (an effect measured by ankle circumference and leg volume), while improving symptoms such as pain, heaviness, and itching. Studies report moderate effectiveness, with a reduction in ankle circumference of about 4.27 mm compared with placebo, as well as a subjective improvement in sensations of heaviness and pain. However, the quality of the data is considered moderate to low due to variability in methodologies and potential biases. The benefits of rutin appear modest and further studies are needed to confirm its effectiveness in managing CVI symptoms.

Hydroxyethylrutosides and other rutoside preparations—synthetic derivatives of rutin often originally sourced from plants like Sophora—have demonstrated improvements in leg swelling, heaviness, cramps, and night pain in chronic venous disease, with reasonable tolerability. This gives indirect support for high-quality Sophora-derived rutin extracts as part of a venous support approach.

Extract of the Japanese pagoda tree has been shown to be effective in the strengthening of vein walls, normalization of the permeability of veins and capillaries, and maintenance of good vein health.

Evidence strength: Moderate-to-low for rutin as a class (Cochrane-reviewed evidence). Direct clinical evidence for S. japonica whole-flower extract specifically remains limited; most evidence derives from rutin-derivative clinical trials that do not employ the crude botanical extract.

5.2 Hemorrhoids and Hemostasis

Sophora japonica has been used in Chinese traditional medicine as a haemostatic agent. Flavones from the buds and pericarp were discovered as haemostatic constituents.

The Chinese Pharmacopoeia's mandatory quality standard specifies that the content of rutin in the dried product must be >60 mg/g (6%), directly confirming the scientific basis for its traditional use as a hemostatic.

In terms of specific human clinical evidence for hemorrhoids, traditional uses and single-ingredient pharmacological studies indicate actions of stopping haemorrhoidal bleeding and an antihypertensive action, with the single ingredients showing decrease of capillary permeability, anti-inflammatory activity, improved coronary circulation, relaxation of bronchial and intestinal muscles, and inhibition of platelet aggregation.

Evidence strength: Preclinical and traditional evidence is strong; robust prospective human RCTs specifically examining S. japonica extract for hemorrhoids remain limited. Combination herbal formulas containing rutin are currently being investigated in registered clinical trials (e.g., ClinicalTrials.gov NCT06705777).

5.3 Oxidative Stress and Body Composition — RCT Evidence

One of the most recent and direct human clinical trials examined a standardized S. japonica extract. A 56-day randomized, double-blind, placebo-controlled, parallel-group, multi-centric clinical trial enrolled individuals aged 30–60 years with BMI ≥25 to ≤34.9 kg/m². 68 participants were randomly allocated to LN-OS-22 (SophorOx®) or placebo groups. The extract was derived from the flower bud of the plant, underwent ethanol/water extraction, and was standardized to contain ≥90% flavonoids, primarily quercetin, rutin, and other minor flavonoids.

To assess oxidative stress, isoprostane was measured as a reliable biomarker of lipid peroxidation and antioxidant deficiency. Results showed that subjects taking SophorOx experienced a significant 600% reduction in isoprostane levels compared to placebo. Secondary endpoints showed that subjects taking SophorOx saw a 13 times greater reduction in BMI, 15 times better weight reduction, and 8 times lower waist circumference compared to placebo.

Evidence strength: Promising preliminary RCT data, but from a single industry-associated trial with a small population (68 participants). Independent replication is needed to confirm body-composition findings. The oxidative stress outcome (isoprostane reduction) is supported by the mechanistic literature on these flavonoids.

5.4 Osteoporosis and Postmenopausal Health

Sophora japonica is a source of several flavonol, flavone, and isoflavone glycosides that are reported to positively affect menopausal symptoms including osteoporotic complications.

In a preclinical study published in PLOS ONE, sophoricoside (SPH) was selected for in-vivo studies as a potential anti-osteoporosis agent. The anti-osteoporotic effect was assessed in ovariectomized (OVX) rats after oral administration at 15 mg/kg and 30 mg/kg for 45 days, compared to estradiol (10 mg/kg) as a positive control. Only at a dose of 30 mg/kg did SPH regain the original mechanical bone hardness compared to the normal non-osteoporotic group. Histopathologically, sophoricoside ameliorated the ovariectomy-induced osteoporosis in a dose-dependent manner.

In a separate animal study, Fructus Sophorae extract (FSE) was administered orally for three months at a dose of 200 mg/kg in ovariectomized New Zealand rabbits. 3D computed tomography scans and histopathological images revealed microstructural disturbances in the bones of the castrated animals. FSE recovered most of the affected bone parameters in a manner similar to zoledronic acid (ZA) used as a positive control.

Both extracts (glycoside-rich and aglycone-rich) exhibited potent anti-inflammatory effects in adipose tissue, suppressing IL-6 and TNF-α, while regulating adipogenesis markers (FABP4, KLF, leptin, PPARγ) more effectively than 17β-estradiol in the ovariectomized rat model.

A randomized double-blind placebo-controlled clinical trial by Lee et al. (2010) examined the effect of Rexflavone (Sophorae fructus extract) on menopausal symptoms in postmenopausal women, referenced in the PMC literature as providing human data, though the specifics of that trial's outcomes are not fully accessible in the searched sources.

Evidence strength: Predominantly preclinical (animal model). The phytoestrogenic mechanism is plausible and mechanistically consistent, but human RCT evidence remains sparse. Research is ongoing.

5.5 Antioxidant Effects

Several flavonoids and isoflavonoids from S. japonica exhibit a wide range of biological activities in vitro and in vivo, including antioxidant and radical scavenging effects. The clinical RCT described above (SophorOx®) demonstrated a significant reduction in 8-isoprostane, a validated biomarker of oxidative stress, providing human-level evidence for antioxidant activity. However, this was a single trial from the ingredient's developer.

Evidence strength: Mechanistically strong in vitro and animal data; supported by one human RCT. Further independent clinical research is needed.

5.6 Anti-inflammatory Activity

Numerous in vivo and in vitro studies have revealed that Flos Sophorae and Flos Sophorae Immaturus extracts display anti-inflammatory activity among other pharmacological effects. Rutin and quercetin have been shown in cell-based and animal studies to modulate NF-κB pathways, inhibit cyclooxygenase enzymes, and suppress pro-inflammatory cytokines including TNF-α, IL-1β, and IL-6.

Evidence strength: Primarily in vitro and animal. Clinical anti-inflammatory evidence in humans for S. japonica specifically is indirect (derived from rutin/quercetin studies). Direct human trials are lacking.

5.7 Antihyperglycemic and Metabolic Effects

In vivo and in vitro studies have revealed that S. japonica extracts display hypoglycemic effects, among other pharmacological properties. Pharmacological activities attributed to constituents include anti-hyperglycemic and anti-diabetic effects. These remain preliminary, based mainly on animal and cell models.

Evidence strength: Preliminary; animal and in vitro evidence only. No robust human RCTs establishing anti-diabetic efficacy for the botanical extract itself.

5.8 Antibacterial and Antiviral Activity

Modern pharmacological research reports that S. japonica exhibits antibacterial and antiviral properties, among other biological effects. Preclinical studies have reported activity against several bacterial strains, with metabolites from S. japonica flowers also showing inhibitory activity against Streptococcus mutans sortase A in in vitro models. These findings are entirely laboratory-based.

Evidence strength: In vitro only. No clinical evidence.

5.9 Antitumor Activity

Flavonoids and isoflavonoids from S. japonica have demonstrated antitumor effects in vitro and in vivo. Quercetin's broad anticancer mechanisms—including induction of apoptosis, inhibition of cell cycle progression, and modulation of signaling pathways—have been extensively studied, though this research spans quercetin as a molecular entity rather than the botanical extract specifically. All evidence is preclinical.

Evidence strength: Preclinical only. No clinical trials for cancer treatment using S. japonica extract.

5.10 Skin Health

Sophora japonica extract appears in cosmetics aimed at redness, pigmentation, and photoaging. In vitro and in vivo studies have revealed skin whitening and skin-protective effects for the extract. The plant is also used as a remedy for skin diseases like eczema, colpitis, and psoriasis, primarily on the basis of its anti-inflammatory and antioxidant flavonoid content.

Evidence strength: Mostly in vitro and traditional. Limited controlled clinical evidence specific to S. japonica extract for skin conditions.

6. Dosage Forms and Reported Dosages

To prevent toxic effects, the 2015 edition of the Chinese Pharmacopoeia recommends a dose of 5–10 g for Flos Sophorae Immaturus and 6–9 g for Fructus Sophorae.

Typical supplemental rutin doses range from about 250–1,000 mg per day, while traditional crude flower use is around 5–10 g daily, always divided and usually short term.

In clinical research contexts, the following dosages have been reported in identified studies:

Preclinical (osteoporosis, OVX rat model): Oral sophoricoside at 15 mg/kg and 30 mg/kg for 45 days.
Preclinical (osteoporosis, OVX rabbit model): Oral Fructus Sophorae extract at 200 mg/kg for three months.
Clinical RCT (oxidative stress/body composition): SophorOx® (standardized to ≥90% flavonoids) administered over 56 days in a double-blind, placebo-controlled, multi-centric trial in adults aged 30–60 years with BMI ≥25 to ≤34.9 kg/m².
Preclinical anti-inflammatory (exercised rats): Oral SophorOx™ at 500 mg/kg body weight administered to Sprague–Dawley rats.

Most rutin dietary supplements are made from the Japanese pagoda tree (Sophora japonica). Standardized commercial extracts are typically standardized to 95–98% rutin or ≥90% total flavonoids. No universally accepted supplemental dosage range for human use has been established in guideline-level documents reviewed.

7. Safety Considerations and Interactions

7.1 Overall Safety Profile

The United States Pharmacopeia (USP) safety review focused on the safety of S. japonicum flower and flower bud as dietary supplement ingredients. No serious adverse events or toxicity were reported in the clinical or experimental animal studies reviewed.

In genetic toxicity testing, the single approximate lethal dose was found to be greater than 2,000 mg/kg in animal studies, indicating a wide safety margin at typical supplemental doses.

Genetic toxicity tests showed no adverse events in an in vitro chromosomal aberration study, bacterial reverse mutation study, and micronucleus test. In addition, clinical trials conducted to check the expression rate of adverse events in subjects found no difference between groups.

7.2 Acknowledged Safety Data Gaps

Information on the side effects and safety evaluations for S. japonica is limited, although this plant is frequently used in TCM. Information on evaluating the safety of S. japonica is very limited, so further study is required. Despite its health benefits, supplementary data is still required in order to bridge the gaps and ensure the possible safety profile by conducting clinical studies for its therapeutic applications.

7.3 Potential Drug Interactions

Although some studies indicated that rutin or quercetin may have potential for drug interactions, none were specifically identified for S. japonicum flower or flower bud in the USP review.

Flavonoids can modulate cytochrome P450 enzymes and drug transporters, potentially altering the levels of medications such as anticoagulants, antiplatelet agents, some chemotherapies, immunosuppressants, and certain blood pressure or cholesterol drugs. The direction of the effect (higher or lower levels) can vary with dose, timing, and the specific medicine.

Regarding anticoagulants specifically, experimental data in rats by Chan et al. (2009) — referenced in the USP safety review — found that rutin affected warfarin pharmacokinetics, reducing the anticoagulant effect of warfarin. This experimental data suggests rutin can reduce warfarin's anticoagulant effect, and warfarin users should consult clinicians and treat this as a high-priority interaction risk.

7.4 Mild Adverse Effects

Mild digestive upset, headache, or skin reactions are possible, and higher flavonoid doses may interact with drugs or stress the liver and kidneys in vulnerable people.

Rutin and quercetin themselves are generally regarded as having low intrinsic toxicity, but they are metabolised and cleared through the liver and kidneys. In people with existing organ impairment, taking multiple polyphenol-rich supplements, high doses over long periods, or combining with hepatotoxic or nephrotoxic drugs may add to overall stress on these organs.

7.5 Special Populations

Pregnant or breastfeeding individuals, children, and people on multiple medications (especially for clotting, cancer, or blood pressure) should avoid self-prescribing Sophora japonica extract.

A separate in vitro study at PubMed (PMID 30802219) examined reprotoxicity concerns: results indicate that Sophora japonica extract induces oxidative/nitrosative stress-mediated impairment of the mechanism for free radicals scavenging, which may provoke genotoxic events in germ cells, by cell cycle arrest and micronuclei in vitro in mouse germ cells. The authors emphasized that toxicological studies are urgently needed to confirm the safety of Sophora japonica extracts for clinical use. These findings are preliminary and limited to an in vitro cell model; they should not be extrapolated directly to human use without further investigation.

7.6 Anaphylaxis Risk

There is one case report of anaphylaxis in a child associated with the plant. This underscores the need for awareness of potential allergic reactions, particularly in individuals with known legume or plant-extract hypersensitivities.

8. Body Systems and Health Domains

Based on the reviewed scientific and ethnopharmacological literature, Sophora japonica is primarily associated with the following body systems and health domains:

Cardiovascular and venous system: Capillary integrity, venous tone, chronic venous insufficiency, antihypertensive effects, platelet aggregation inhibition.
Hematological: Hemostasis, control of hemorrhoidal, uterine, and gastrointestinal bleeding.
Musculoskeletal / endocrine: Bone remodeling and anti-osteoporotic activity via phytoestrogenic mechanisms (sophoricoside/genistein); postmenopausal health.
Metabolic: Antioxidant status, lipid peroxidation reduction, preliminary antihyperglycemic and anti-obesity activity.
Dermatological: Anti-inflammatory and skin-protective applications; traditional use for pyoderma, eczema, and psoriasis.
Immune and inflammatory: Anti-inflammatory cytokine modulation, immunomodulatory polysaccharide activity.

The flower buds and fruits of S. japonica exhibit a wide range of pharmacological actions, such as cardiovascular effects as well as anti-inflammatory, anti-osteoporotic, antioxidant, antitumor, antibacterial, antiviral, hemostatic, and anti-atherosclerotic effects.

References

Health Conditions

Health conditions that Japanese sophora may help support.

No conditions available.

Body Systems

Body systems that Japanese sophora may help support.

No body systems available.