Phyllanthus

Synopsis

Phyllanthus: A Comprehensive Reference

1. Identity and Botanical Classification

Phyllanthus is a large and taxonomically diverse genus of flowering plants. The genus Phyllanthus belongs to the family Phyllanthaceae and comprises over 2,000 species distributed across tropical and subtropical regions of the world. This genus includes trees, herbs, and shrubs that are pharmacologically important because they contain different bioactive compounds.

The genus was first formally described by Carl Linnaeus, and the taxonomic order is Malpighiales, family Phyllanthaceae. The circumscription of this genus has been a cause of much confusion and disagreement. Molecular phylogenetic studies have shown that Phyllanthus is paraphyletic over Reverchonia, Glochidion, Sauropus, and Breynia. A 2006 revision of the family Phyllanthaceae subsumed all four of these genera into Phyllanthus.

In commerce and research, the term "Phyllanthus" most commonly refers to a handful of closely related medicinal species, particularly the following:

Phyllanthus niruri L. — Often called chanca piedra (Spanish: "stone-breaker"), bhuiamalki, zhuzicao, dukung anak, and quebra-pedra. Its whole plant can treat inflammation, lithiasis, fever, malaria, hepatitis, and gonorrhea.
Phyllanthus amarus Schumach. & Thonn. — Commonly known in Traditional Chinese Medicine (TCM) as Yexiazhu (叶下珠, Yè xià zhū), it is a widely used medicinal herb in Asian, African, and South American traditional systems. It is an erect, glabrous annual herb that typically grows between 0.1 and 0.6 m in height.
Phyllanthus emblica L. (syn. Emblica officinalis Gaertn.) — Commonly known as emblic, Indian gooseberry, amalaki, amloki, or amla, it is a deciduous tree of the family Phyllanthaceae whose native range is tropical and southern Asia. It produces edible, nearly spherical drupaceous fruits renowned for their exceptionally high vitamin C content, up to 720 mg per 100 g of fresh weight.
Phyllanthus urinaria L. — An annual perennial herbal species found in tropical Asia, America, China, and the Indian Ocean islands, used in folk medicine as a cure to treat jaundice, diabetes, malaria, and liver diseases.
Additional medicinally investigated species include P. fraternus, P. maderaspatensis, P. debilis, P. simplex, P. polyphyllus, P. reticulatus, and P. indofischerii, among others.

Species studied include Phyllanthus amarus, P. urinaria, P. fraternus, P. maderaspatensis, P. simplex, P. emblica, P. debilis, P. tenellus, P. polyphyllus, P. reticulatus, P. indofischerii, P. acidus, P. niruri, P. rheedii, P. kozhikodianus, and P. longiflorus.

Note on nomenclature: Classical Chinese materia medica does not always distinguish clearly among Phyllanthus species, and modern pharmacognostic and phytochemical studies increasingly support the therapeutic rationale underlying these traditional applications. Many older and popular-use references use "Phyllanthus niruri" in a broad, collective sense that may encompass P. amarus and P. debilis depending on the geographic region and source material used.

Common Preparations and Dosage Forms

In TCM, Yexiazhu is commonly administered as aqueous decoctions, granules, or concentrated extracts, either as a single herb or in combination with other medicinal plants in Chinese herbal prescriptions. In other regional traditions, the whole plant, leaves, roots, and fruits are used as fresh material, dried powder, infusions (teas), and hydroalcoholic (ethanolic) extracts.

In one Brazilian clinical study evaluating effects in patients following extracorporeal shock wave lithotripsy, patients underwent therapy with Uriston®, a P. niruri extract at 2 gm daily for at least 3 months.

Randomized control trials using Phyllanthus emblica for glycaemic control have administered it as a fruit, in powder form, or as a capsule.

In one clinical study, 21 non-insulin-dependent diabetic patients were given twice-daily 100 mL Phyllanthus amarus aqueous extract (from 12.5 g dried aerial parts) for one week, after washout from oral hypoglycemics.

In another single-arm study, 48 participants were recruited to take 225 mg capsules of P. niruri dried leaf extract mixed with 152 mg magnesium stearate and 2 mg pyridoxine hydrochloride (vitamin B6) for 3 months.

One prospective metabolic study examined 56 patients with kidney stones <10 mm. Clinical, metabolic, and ultrasonography assessment was conducted before (baseline) and after the use of a P. niruri infusion for 12 weeks.

2. Traditional and Historical Use

Phyllanthus has been used in Ayurvedic medicine for over 2,000 years and has a wide number of traditional uses including internal use for jaundice, gonorrhea, frequent menstruation, and diabetes, and topical use as a poultice for skin ulcers, sores, swelling, and itchiness.

These plants have a long-standing history of use in traditional medicine, particularly in Asian, African, and South American cultures. The plants of the genus Phyllanthus have been used as traditional medicinal materials for a long time in China, India, Brazil, and Southeast Asian countries for the treatment of digestive disease, jaundice, and renal calculus.

Ayurveda and the Indian Subcontinent

Genus Phyllanthus has been employed as herbal drugs for a long time in China, India, Brazil, and Southeast Asian countries. The most abundant species are used in India and have a beneficial role in Ayurveda for the treatment of digestive, genitourinary, respiratory, and skin diseases.

In many tropical countries where it is cultivated, P. amarus has a long-standing history of use in traditional medicine systems. In Ayurvedic literature, it is recognized for multiple therapeutic roles, such as Raktapittahara (treats hemorrhagic conditions), Paanduhara (antianemic), Kaamalaahara (cures jaundice), Kushthaghna (used in leprosy), and Kshatakshayaghna (used for trauma).

The Phyllanthus genus is a very important plant traded as a raw herbal medicine in India. Commonly known as 'Bhumyamalaki', Phyllanthus species have been used for the prevention and treatment of jaundice.

The fruit of P. emblica has a long history of use in India and is called "amla" or "Indian gooseberry." As a tonic in Indian Ayurveda, it is often used for liver diseases. P. emblica is commonly used together with Terminalia chebula and T. belerica and called "Triphala," used as a clinical treatment protocol of gastropathy in India and as a remedy for pestilence and fatigue in China.

Traditional Chinese Medicine (TCM)

In China, herbs and their prescriptions are used to treat hepatitis B, hypertension, dropsy, and sore throat. In TCM practice, Yexiazhu is traditionally prescribed for heat-clearing and detoxification, particularly in the management of liver-and kidney-related disorders, viral infections, and inflammatory conditions.

The fruit of P. emblica is known as "yuganzi" in China. It has a sweet and slightly astringent taste and is used for clearing heat from the throat and moistening the lung for arresting cough in TCM. In Tibetan medicine, this herb is used to treat blood and bile disease, and its preparations are clinically applicable to hypertension and anuria. In Thailand, it is named "makham pom" and is employed to treat gastrointestinal chronic diseases.

Africa

In Africa, six herbs are widely employed by many tribes for the treatment of malaria, wound, and tetanus.

Latin America and Brazil

Phyllanthus niruri, popularly known as "stone-breaker" ("quebra-pedras"), is a plant belonging to the Euphorbiaceae family with a worldwide distribution and is used in folk Brazilian medicine for patients with urolithiasis. Six species are used extensively in Latin America for the treatment of urination disorder and diabetes.

Southeast Asia

In Asia, seventeen plants are considered to have bitter and astringent taste. They are regarded as stomachic, diuretic, febrifuge, deobstruent, and antiseptic agents and effective remedies for hepatopathy, hypertension, diabetes, and jaundice.

Phyllanthus species are used in constant traditional medications to cure an array of human diseases including constipation, arthritis, loss of appetite, conjunctivitis, diarrhea, malaria, blennorrhagia, colic, diabetes mellitus, dysentery, indigestion, fever, gout, jaundice, hepatic disorders, leucorrhea, menstrual irregularities, obesity, stomach pains, and tumors.

3. Key Constituents and Active Compounds

More than 510 compounds have been isolated from Phyllanthus, the majority of which are lignins, triterpenoids, flavonoids, and tannins. Lignins and tannins exhibit various activities and are considered to be the biological active compounds of this genus. Corilagin, geraniin, and gallic acid are three of the most prevalent compounds in this genus, and pharmacological research mainly focuses on phyllanthin, niranthin, and geraniin.

Lignans

Lignans are regarded as among the most pharmacologically significant class of compounds in Phyllanthus. Contemporary phytochemical investigations have revealed that P. amarus is rich in biologically active constituents, including lignans such as phyllanthin and hypophyllanthin, hydrolysable tannins such as geraniin and corilagin, flavonoids including quercetin derivatives, and various alkaloids.

Hypophyllanthin is a major lignan present in various Phyllanthus species and has been used as one of the bioactive chemical markers for quality control purposes as it contributes to their diverse pharmacological activities. The highest amount of hypophyllanthin was found in the extract of P. amarus (0.383% w/w), while the compound was present at lower concentrations in P. maderaspatensis L. (0.013% w/w) and P. virgatus (0.012% w/w).

Phyllanthin, which has been studied most extensively, is considered to be correlated with anti-inflammatory, immunomodulatory, antitumor, and hypotensive activities.

The lignan phyllanthin renders hepatoprotective property to P. amarus. However, P. fraternus, P. maderaspatensis, and P. urinaria do not contain phyllanthin but are hepatoprotective, and therefore phyllanthin being the sole compound contributing to hepatoprotective property needs to be further investigated.

Tannins

Hydrolyzable tannins are characterized by the presence of one or more galloyl, hexahydroxydiphenoyl (HHDP), and HHDP metabolites attached to a glucopyranose core, and are mainly isolated from P. emblica, P. amarus, P. niruri, and related species. Key tannins identified include geraniin, corilagin, gallic acid, ellagic acid, phyllanthusiin, and chebulagic acid.

Geraniin demonstrated the strongest inhibitory activity on chemotaxis of polymorphonuclear leukocytes (PMNs) and monocytes with IC₅₀ values of 1.09 and 1.69 μM, respectively, which were lower than that of ibuprofen. Geraniin and corilagin exhibited exceptionally strong inhibition on reactive oxygen species (ROS) activity with IC₅₀ values lower than aspirin.

Flavonoids

Detailed explorations of the phenolic compounds in P. acuminatus and P. niruri unravelled the presence of nearly 40 different phenolic derivatives, including pinocembrin isomers, apigenin derivatives, chrysin, quercetin, kaempferol, ellagitannins, prodelphinidin B dimer, epi-gallocatechin, ellagic acid, trimethylellagic acid, and ferulic acid.

Terpenoids

About 125 terpenoid compounds including 69 triterpenoids, 40 sesquiterpenes, 11 diterpenoids, and 5 monoterpenes are mainly identified from the genus. Terpenoids are the most prevalent chemical class numerically across the genus.

Alkaloids

Phyllanthus species are rich in phytochemical diversity, with compounds such as tannins, phenylpropanoids, terpenoids, phenolic compounds, flavonoids, alkaloids, saponins, and many of their glycosides. Alkaloids including securinine and norsecurinine have been documented, though their specific pharmacological roles are still under investigation.

Notable Compounds in P. emblica

Phyllanthus emblica is one of the richest sources of natural vitamin C. It bears stone fruits with immense antioxidant properties due to being one of the richest natural sources of vitamin C and numerous flavonoids. The presence of three ascorbate biosynthesis pathways, including L-galactose, galacturonate, and myo-inositol pathways, has been confirmed in its genome.

4. Established Mechanisms of Action

Antiviral Activity

Antiviral activity against hepatitis B virus has been attributed to inhibition of viral DNA polymerase activity, suppression of HBV gene expression, and modulation of host transcription factors.

The antiviral property of P. amarus has been attributed to the compounds niranthin, nirtetralin, hinokinin, geraniin, and corilagin. Geraniin is a common compound found in P. amarus, P. urinaria, and P. virgatus, which shows antiviral property in all three herbs.

Phyllanthus amarus exhibits significant antiviral properties, particularly against HIV. Extracts from the plant have been shown to inhibit HIV-1 attachment and the activity of key enzymes such as integrase and reverse transcriptase, demonstrating effectiveness both in vitro and in vivo.

Anti-inflammatory Activity

An ethanolic extract of P. amarus has been studied for its effects on pro-inflammatory mediators release in nuclear factor-kappa B (NF-κB), mitogen-activated protein kinase (MAPK), and phosphatidylinositol 3-kinase/Akt (PI3K-Akt) signaling activation in lipopolysaccharide (LPS)-induced U937 human macrophages.

Several lignans isolated from P. amarus such as niranthin, nirtetralin, and phyltetralin exhibited in vitro and in vivo anti-inflammatory activities.

Anti-inflammatory activity in P. urinaria is attributed to the phytochemicals phyltetralin, phyllanthin, quercetin, rutin, rhamnocitrin, and β-sitosterol.

Antioxidant Activity

Antioxidant activity is shown by rutin, quercetin-3-O-glucoside (flavonoids), phyllanthin (lignan), amariin, repandusinic acid A, corilagin, phyllanthusiin A, B, C, geraniin (ellagitannins), methyl brevifolin (coumarin), methyl gallate, and trimethyl 1-3,4-dehydrochebulate (triterpenes).

Immunomodulatory Activity

Hypophyllanthin, together with other major components of the extracts especially geraniin, corilagin, and phyllanthin, could be the major contributors to the strong immunomodulatory effect of the plant extracts as they were able to modulate the innate response of phagocytes at different steps.

Hypophyllanthin and phyllanthin were found to exhibit potent inhibitory action on both phagocytic activity and CD18 expression of phagocytes.

Hepatoprotective Mechanisms

Metabolites such as phyllanthin, hypophyllanthin, 8,9-epoxy brevifolin, brevifolin, quercetin, gallic acid, ellagic acid, and brevifolin carboxylate have been shown to have hepatoprotective and antioxidant activity.

Antidiabetic Mechanisms

By increasing the activities of glycolytic enzymes and lowering the activities of gluconeogenic and lipogenic enzymes in the liver of alloxan-induced diabetic rats, P. amarus extract has been shown to restore glucose homeostasis. P. amarus leaves have also been shown to exhibit anti-diabetic properties by controlling carbohydrate metabolism and lowering oxidative stress. P. amarus has been shown to have an anti-hyperglycemic impact via phosphorylating IRS and IR, which stimulates the insulin signaling pathway. In vitro research indicates that GLUT4 translocation to the plasma membrane contributes to P. amarus's hypoglycemic impact.

5. Scientific Evidence by Area of Use

5.1 Hepatoprotection and Liver Disease

The hepatoprotective properties of Phyllanthus are among the most extensively studied aspects of the genus. Species studied, including P. amarus, P. urinaria, P. fraternus, P. maderaspatensis, P. simplex, P. emblica, P. debilis, P. tenellus, P. polyphyllus, P. reticulatus, P. indofischerii, P. acidus, P. niruri, P. rheedii, P. kozhikodianus, and P. longiflorus, had considerable hepatoprotective potential.

Evidence strength: Weak-to-moderate in vitro and animal evidence; insufficient high-quality clinical evidence.

5.2 Chronic Hepatitis B Virus (HBV) Infection

This is the most clinically examined area for Phyllanthus, with two Cochrane systematic reviews available.

There is no convincing evidence that Phyllanthus compared with placebo benefits patients with chronic HBV infection. Phyllanthus plus an antiviral drug may be better than the same antiviral drug alone. However, heterogeneity, systematic errors, and random errors question the validity of the results.

More specifically, Phyllanthus did significantly affect serum HBV DNA (RR 0.69; 95% CI 0.52 to 0.91, P = 0.008; I² = 71%), serum HBeAg (RR 0.70; 95% CI 0.60 to 0.81, P < 0.00001; I² = 68%), and HBeAg seroconversion (RR 0.77; 95% CI 0.63 to 0.92, P = 0.005; I² = 78%), but the heterogeneity was substantial.

A second Cochrane review comparing Phyllanthus directly against antiviral drugs found that Phyllanthus seemed to have a superior effect on clearance of serum HBeAg at end of treatment in conventional meta-analysis (RR 0.76; 95% CI 0.64 to 0.91, P = 0.002; I² = 0%), but not when trial sequential analysis was applied. Phyllanthus had no significant effect on clearance of serum HBsAg (RR 1.00; 95% CI 0.93 to 1.08) or HBV DNA (RR 0.83; 95% CI 0.53 to 1.31) when compared with antiviral drugs.

There is currently insufficient evidence to support or refute the use of Phyllanthus for patients with chronic hepatitis B virus infection. A major limiting factor is that all of the trials evaluated were of low methodology quality, i.e., have high risk of bias, and there was a risk of random errors in the majority of comparisons. None of the trials reported mortality and hepatitis B-related morbidity, quality of life, or liver histology.

Evidence strength: Inconclusive. Multiple randomized trials exist but all carry high risk of bias; Cochrane reviews find no convincing benefit over placebo.

5.3 Urolithiasis (Kidney Stones)

Phyllanthus niruri (P. niruri) is the most commonly listed active ingredient in commercially available herbal therapies for kidney stones, despite limited supporting clinical evidence.

In a comprehensive review of the literature, Phyllanthus niruri was shown to interfere with calcium oxalate crystallization while at the same time reducing hyperoxaluria and hyperuricosuria.

One prospective Brazilian study studied 56 patients with kidney stones <10 mm. Clinical, metabolic, and ultrasonography assessment was conducted before and after the use of a P. niruri infusion for 12 weeks, followed by a 12-week washout period. Results showed no significant changes in anthropometric and several serum measurements, including creatinine, uric acid, sodium, potassium, calcium, urine volume, and pH, but a significant increase in urinary potassium from 50.5±20.4 to 56.2±21.8 mg/24-hour (p=0.017) and magnesium/creatinine ratio from 58±22.5 to 69.1±28.6 mg/gCr24-hour (p=0.013).

A randomized study evaluated the efficacy of P. niruri after extracorporeal shock wave lithotripsy: 150 patients with renal stones as large as 25 mm composed of calcium oxalate were prospectively evaluated. After treatment, 78 of 150 patients (52%) underwent therapy with Uriston®, a P. niruri extract (2 gm daily) for at least 3 months (group 1), while 72 of 150 patients (48%) were used as a control group. No significant difference in stone size between the two groups was found.

Altogether, studies suggest a preventive effect of Phyllanthus niruri in stone formation or elimination, but longer-term randomized clinical trials are necessary to confirm its therapeutic properties.

Limited clinical evidence supports modest efficacy of P. niruri in reducing stone burden, pending further study.

Evidence strength: Preliminary and inconsistent. Pre-clinical and in vitro data are more promising than human clinical data. Available human trials are small and of limited quality.

5.4 Diabetes and Glycemic Control

Phyllanthus species have been known for their medicine and food homology properties in the management of diabetes and related metabolic disorders. The overview of phytochemical fingerprints and bioactive compounds in Phyllanthus plants, and the elucidation of biomarker pathways, has deepened the understanding of antidiabetic properties of these medicinal plants.

One small clinical study used a P. amarus aqueous extract: short-term administration showed no hypoglycemic effect in humans, and no serious adverse effects on liver/kidney function were noted, though minor shifts in white cell fractions were observed. Another investigation examined 9 mild hypertensive subjects (4 with diabetes) treated for 10 days with a whole-plant preparation. Significant reductions in blood glucose levels and systolic blood pressure were observed in non-diabetic hypertensives, and no harmful side effects were noted.

For P. emblica (amla) specifically, a systematic review on the Scopus database identified 8 articles eligible for inclusion from a targeted search. Data from 2010 to 2025 for in vitro and in vivo antidiabetic studies demonstrated the capability of Phyllanthus species as anti-hyperglycemic agents. However, robust large-scale human RCTs are still lacking.

Evidence strength: Predominantly preclinical (animal and in vitro). Human clinical data are sparse, involve small samples, and short durations. No established clinical role as an antidiabetic agent can be claimed from current evidence.

5.5 Anti-inflammatory Effects

P. amarus has received increasing attention and has been studied for various pharmacological properties such as immunomodulatory, antinociceptive, anti-inflammatory, antioxidant, antibacterial, anticancer, antiulcer, gastroprotective, antifungal, antiplasmodic, antiviral, aphrodisiac, contraceptive, hepatoprotective, antihyperglycemic, antilipidemic, nephroprotective, and anti-amnesic activities. Although it demonstrates a wide spectrum of pharmacological actions, the unifying features of all these actions are directed towards the anti-inflammatory and antioxidant properties of the plant.

Preclinical evidence for anti-inflammatory activity is consistent, with demonstrated inhibition of NF-κB, MAPK, and PI3K-Akt pathways. However, all such evidence is from cell and animal studies, with no controlled human trials reported to date specifically for inflammation-related end-points.

Evidence strength: Solid preclinical (in vitro and animal) evidence for anti-inflammatory mechanisms; no dedicated human clinical trials for an inflammatory condition.

5.6 Antioxidant Effects

Consistent with ethnopharmacology, numerous modern studies have demonstrated that the extracts or monomeric compounds derived from P. emblica fruits exhibit various pharmacological effects including anti-oxidation, anti-bacteria, anti-inflammation, anti-tumour, anti-virus, immunity improvement, hypoglycemic and hypolipidemic effects, and multiple organ protection.

The high vitamin C content of P. emblica fruit (Indian gooseberry / amla) is one of the most consistently cited antioxidant features. The genus more broadly contains multiple antioxidant-active polyphenols. These findings are largely based on in vitro assays and animal models; dedicated human clinical trials for antioxidant outcomes are limited.

Evidence strength: Strong in vitro data; limited human clinical evidence for specific antioxidant end-points.

5.7 Anticancer Activity

Isolated compounds from Phyllanthus lathyroides exhibited moderate to good antiproliferative activity (IC₅₀ < 20 µM) with selectivity to SiHa (cervical carcinoma) cells. These findings highlight the potential of Phyllanthus species as sources of novel anticancer agents, with specific arylnaphthalide lignans showing promising cytotoxic effects.

For example, P. emblica has demonstrated growth inhibitory activity on A549 and HepG2 (liver carcinoma) cell lines, while the toxicity of P. polyphyllus on MCF-7, HT-29 (colon adenocarcinoma), and HepG2 was also reported.

Evidence strength: Entirely preclinical (in vitro cell line studies and animal models). No human clinical trials on Phyllanthus for cancer have been identified. These findings are exploratory only.

5.8 Immunomodulation

Phyllanthus species have been widely investigated for various biological and pharmacological activities including antioxidant, antiviral, antibacterial, anti-inflammatory, anticancer, hepatoprotective, antimalarial, antiplasmodial, antidiabetic, nephroprotective, hypolipidemic, and diuretic activities. The most intensively investigated bioactive metabolites include corilagin, geraniin, gallic acid, phyllanthin, hypophyllanthin, ellagic acid, phyltetralin, niranthin, catechin, quercetin, astragalin, and chebulagic acid.

Although suppressive effects of the plants are promising for their further development into immunosuppressive agents, their potential adverse effects in clinical applications have to be considered. The underlying mechanisms involved in the immunomodulatory effects of the Phyllanthus species were not in-depth studied due to limitations in terms of design, conduct, and interpretation.

Evidence strength: Preclinical only. No human immunomodulatory clinical trials identified.

5.9 Antihypertensive Effects

A small investigation examined 9 mild hypertensive subjects (4 with diabetes) treated for 10 days with a whole-plant preparation, finding significant reductions in systolic blood pressure in non-diabetic hypertensives, with no harmful side effects observed. This study is limited by very small sample size, short duration, and the lack of a control group as described.

Evidence strength: Extremely limited human data. Preclinical evidence for antihypertensive mechanisms exists but clinical trials are essentially absent.

6. Body Systems and Health Areas Associated with Phyllanthus

Hepatobiliary system: Hepatoprotection, liver enzyme modulation, anti-hepatitis activity (HBV, HCV)
Urinary/renal system: Kidney stone prevention and dissolution, diuretic, nephroprotective
Endocrine/metabolic system: Antidiabetic, antihyperlipidemic, anti-hyperuricemic
Immune system: Immunomodulation, antiviral (HBV, HIV, HSV), antimicrobial
Cardiovascular system: Antihypertensive, hypolipidemic
Gastrointestinal system: Antiulcer, gastroprotective, antidiarrheal, digestive aid
Integumentary system: Topical anti-inflammatory, wound healing (traditional)
Oncology: Antiproliferative, cytotoxic (in vitro/preclinical only)

Extracts and isolated compounds from P. amarus show a wide spectrum of pharmacological activities including antiviral, antibacterial, antiplasmodial, anti-inflammatory, antimalarial, antimicrobial, anticancer, antidiabetic, hypolipidemic, antioxidant, hepatoprotective, nephroprotective, and diuretic properties.

7. Dosage Forms Reported in Studies

Dosage forms and regimens for Phyllanthus vary considerably across studies, reflecting the diversity of species, parts used, and preparations. Only figures as reported in the referenced literature are listed here:

21 non-insulin-dependent diabetic patients were given twice-daily 100 mL Phyllanthus amarus aqueous extract (from 12.5 g dried aerial parts) for one week.
In a post-lithotripsy study, P. niruri extract (Uriston®) was given at 2 gm daily for at least 3 months.
In a single-arm kidney stone study, 48 participants took 225 mg capsules of P. niruri dried leaf extract mixed with 152 mg magnesium stearate and 2 mg pyridoxine hydrochloride (vitamin B6) for 3 months.
A prospective metabolic study examined 56 patients with kidney stones <10 mm who consumed a P. niruri infusion for 12 weeks.
In animal anti-inflammatory studies, methanol extract of P. niruri leaves was evaluated at the doses of 100, 200, and 400 mg/kg, p.o., using ibuprofen (20 mg/kg, p.o.) as a standard comparator.

No universally accepted standardized dosage for any species of Phyllanthus has been established by a regulatory body such as the WHO or EMA for any specific indication.

8. Safety Considerations and Interactions

General Toxicological Profile

The lack of adequate scientific evidence on the safety of P. niruri is often a major issue to the acceptance and use of this medicinal plant. However, available acute toxicity data in animals have generally been reassuring:

The absence of toxidromes was evident at the time of extract administration and thereafter. The biochemical data, mainly from hepatobiliary and renal systems, did not suggest any toxicity.

Toxicological studies on Phyllanthi Fructus (P. emblica fruits) indicated the absence of any adverse effects even at a high dose after oral administration.

Toxicological data revealed that lower dosages of Phyllanthus species are safe for consumption without significant adverse effects.

Clinical Trial Adverse Event Data

In the Cochrane HBV review, only two trials reported adverse events with numbers, without significant differences. No serious adverse events were reported.

In the single human diabetes study involving P. amarus aqueous extract, no serious adverse effects on liver/kidney function were found, though minor shifts in white cell fractions were noted.

Standardization and Quality Issues

Deficiencies such as under-reporting of adverse reactions, general lack of toxicological information on herbs, and the quality of the reported information present challenges when signals of safety concern arise.

Despite strong experimental support from in vitro and in vivo models, clinical findings remain limited, heterogeneous, and occasionally inconsistent, particularly for hepatitis B and metabolic disorders.

Immunomodulatory Concerns

Although suppressive effects of the plants are promising for their further development into immunosuppressive agents, their potential adverse effects in clinical applications have to be considered. Extracts that modulate immune function could theoretically interact with immunosuppressive medications or autoimmune therapies, though direct human evidence for such interactions is not yet established.

Reproductive Concerns

Animal studies have examined effects on reproductive parameters (see cited literature), though the clinical significance in humans remains undetermined from available evidence. Traditional use systems in some regions caution against use during pregnancy, consistent with general precautions for unstudied botanical agents in pregnancy.

Drug Interaction Potential

Given the broad pharmacological activity documented — including effects on liver enzymes, glucose metabolism, immune function, and platelet aggregation in preclinical models — the theoretical potential for herb-drug interactions exists with antivirals, antidiabetic agents, antihypertensives, and anticoagulants. Phytochemical composition including lignans, alkaloids, flavonoids, and polyphenols contribute to hepatoprotective, antiviral, and antioxidant activities that could influence the pharmacokinetics or pharmacodynamics of co-administered drugs. Formal human pharmacokinetic interaction studies have not been published to date for most Phyllanthus preparations.