Wrightia tinctoria

Other Names

AjamaraAkupalaAllamanda verticillata Desf.Alstonia oleandrifolia Lodd. ex G.DonAmkudaAnkuduAnkuduchettuAsita KutajaAyyappalaBepalliBhanthappaalaBhurevadaBlack indrajauChiti-anikuduChittankuduDandappalaDhanthappalaDodda pala chettuDudhaloDudhiDyeing rosebayDyer's oleanderGode IndarjavaGode indrajavaHayamarakaIndar jao shirinIndarjao MithaIndarjua shireenIndrajao shirinIndrajauIndrajavIndrajavaIndrayavaIrumpaalaiIvory treeIvory woodJedda pala chettuJeddapalaKala kudaKalakudaKalakudoKambippalaKampippaalaKarayajaKirikodasigeKodamurkiKondajemuduKota kappalaKudaLansanul-aasafirMadhuindrajavaMitha IndarjavaMitha indrajauNeelappalaNerium jaspideum Span.Nerium tinctorium Roxb.Nerium tinctorium SweetNilapaalaiNilappalaPala indigo plantPunkutajaReppalaStri KutajaSvetakutajaSweet indrajaoTedlapalaTella palaVapaalaiVeppaalaiVetpalaiVettupalaWrightia indica DalzellWrightia laciniata A.DC.Wrightia mollissima A.DC.Wrightia timorensis Miq.Wrightia tinctoria (Roxb.) R.Br.Wrightia tinctoria subsp. rothii (G.Don) NganWrightia tinctoria subsp. tinctoria

Synopsis

Wrightia tinctoria (Roxb.) R.Br.: A Comprehensive Reference

1. Identity, Botanical Classification, and Common Names

Botanical Classification

Wrightia tinctoria, known as the Pala indigo plant or dyer's oleander, is a flowering plant species in the genus Wrightia found in India, Southeast Asia, and Australia. It is a small deciduous tree belonging to the family Apocynaceae. The accepted scientific binomial is Wrightia tinctoria (Roxb.) R.Br., where the species epithet tinctoria (Latin: "relating to dyeing") reflects its historical use as a source of indigo-like pigment. The genus Wrightia is named after a Scottish physician and botanist William Wright (1740–1827).

Botanical Synonyms

The following are considered synonyms of Wrightia tinctoria: Allamanda verticillata Desf., Alstonia oleandrifolia Lodd., Nerium jaspideum Span., Cerium tinctorium Roxb., Wrightia laciniata A.DC., and Wrightia timorensis Miq.

Common and Vernacular Names

Known by various names, common English names include Ivory Tree, Easter Tree, Sweet Indrajao, and Pala Indigo Plant. In India, it is locally recognized by its different vernacular names, the most commonly used ones being Indrajava, Svetkutaja, and Krsnkutaja (Sanskrit), Kalakuada (Marathi), and Mitha Indrajau (Hindi). In the context of traditional medicine, Wrightia tinctoria is often referred to by its Sanskrit name, Svetakutaja or Shveta Kutaja (White Kutaja), to differentiate it from Holarrhena antidysenterica (Kutaja). In south India, the plant is also known as the "jaundice curative tree."

Morphology and Habitat

The plant is a small to medium-sized deciduous shrub or tree, ranging from 3–15 m (10–49 ft) in height, and the bark is smooth, yellowish-brown and about 10 mm thick, producing a milky-white latex. Leaves are simple, oppositely arranged, ovate, obtusely acuminate, and are 10–20 cm long and 5 cm wide; they are glabrous and sometimes pubescent beneath. The flowers appear in India from March to May, peaking from April to June; white flowers appear in corymb-like cymes, 5–15 cm across, at the ends of branches.

Wrightia tinctoria is primarily found in the plains and lower hills of India, extending into parts of Southeast Asia including Sri Lanka, and Australia. It is prevalent in dry deciduous and moist deciduous forest types. Within its broader range, it is distributed in India, Australia, Myanmar, Nepal, and Timor, Vietnam. Within India, it is found in most of the peninsular and central India except the northern and northeastern states.

Adulteration and Confusion with Related Species

Wrightia tinctoria has often been confused with Holarrhena antidysenterica, another member of the same botanical family. The properties of W. tinctoria are considered to be the same as those of Holarrhena antidysenterica in Ayurvedic literature, which has contributed to historical and commercial adulteration. This adulteration has been recognized as a matter of pharmacognostical concern in scientific literature.

Common Preparations and Dosage Forms

In traditional medicine, almost all parts of the plant, including the leaves, bark, seeds, and even the milky juice, are utilized for various ailments. The most widely encountered modern preparations include:

Leaf oil (Vetpalai Thailam / "777 Oil"): "777 oil" is a code drug of the Siddha system of medicine used in the treatment of psoriasis. The drug is derived from the leaves of Wrightia tinctoria by insolation, with coconut oil as the base.
Standardized extracts and emulsions: A formulation with the trade name RegSoR® contains Wrightia tinctoria and Cocos nucifera as main components for the treatment of psoriasis vulgaris.
Aqueous, methanolic, and ethanolic leaf/bark extracts: Used extensively in laboratory research; the solvent system affects the phytochemical yield and activity profile.
Decoctions, powders, and poultices: Used in traditional practice from bark, leaves, roots, and seeds for gastrointestinal, dermatological, and systemic conditions.

2. Traditional and Historical Use

Ayurvedic Tradition (India)

Different parts of Wrightia tinctoria R.Br. (Apocynaceae) have been extensively used in Indian systems of medicine such as Ayurveda, Siddha, and Unani for the treatment of jaundice, malaria, psoriasis, and many other ailments. In the Ayurvedic system, the principle of drug action of W. tinctoria is described as tikta (bitter), kashaya (astringent), rooksha (dry), sita (cool), and katu (pungent). In Ayurvedic terminology, the plant is classified as: Rasayana (tonic, generally promoting health and vitality), Vajikarana (aphrodisiac, used to enhance sexual vigor), Jwaraghna (febrifuge, reducing fever), antidysenteric (used to treat dysentery and diarrhea), and anthelmintic (used to expel intestinal worms).

The term Indrayava (or Indrajava) specifically refers to the seeds, which are highly valued medicinally. The juice of the tender leaves was used efficaciously in jaundice. Crushed fresh leaves, when filled in the cavity of a decayed tooth, were used to relieve toothache.

Siddha Tradition (South India / Tamil Nadu)

In the Siddha system of medicine, the plant is used for psoriasis and other skin diseases. Oil 777, prepared out of the fresh leaves of the plant, has been assigned analgesic, anti-inflammatory, and anti-pyretic activities and is considered effective in the treatment of psoriasis. The early Siddha clinical study by Krishnamurthy JR, Kalaimani S, and Veluchamy G on vetpalai (Wrightia tinctoria L.) oil in the treatment of kalanjagapadai (psoriasis), published in the Journal of Research in Ayurveda and Siddha in 1981, is cited widely as foundational historical evidence for the Siddha use of leaf oil in dermatological conditions.

Folk and Tribal Uses

Traditionally, the plant is used to treat seizures, wounds, jaundice, leukaemia, gynaecological disorders, toothache, headache, dandruff, diarrhoea, and skin disorders like psoriasis, eczema, and scabies. In folk medicine, the dried and powdered roots of Wrightia along with Phyllanthus amarus (Keezhanelli) and Vitex negundo (Nochi) is mixed with milk and orally administered to women for improving fertility. The leaves are also applied as a poultice for mumps and herpes. In Sri Lanka, the plant is called "Purugal," with its bark combined with other bitter herbs to combat dysentery.

Non-Medicinal Historical Uses

The seeds, roots, and leaves furnish an indigo-yielding glucoside used for dyeing cloth. It yields a natural blue dye (Pala Indigo) from its leaves, seeds, and roots, requiring 100–200 kg of leaves to produce 1 kg of dye, and its light, fine-textured wood is used for carving and furniture, while the latex contains 2–28% rubber content.

3. Key Phytochemical Constituents

Overview of Chemical Classes

Wrightia tinctoria shows the presence of phytochemical constituents including steroids, triterpenoids, saponins, tannins, phenols, flavonoids, glycosides, carbohydrates, alkaloids, and polyphenols; these phytochemicals are considered responsible for the various pharmacological and medicinal properties of the plant.

Indole Alkaloids and Related Nitrogen Compounds

The plant is rich in compounds containing alkaloids, saponins, indoxy-yielding O-glycoside(s), phenolics, flavonoids, isatin, tryptanthrin, anthranilate, rutin, β-isatin, tryptophan, indigotin, indirubin, wrightial, and sterols. Indigotin (indigo blue) and indirubin (the red isomer of indigo) are structurally related bisindole pigments that form from the oxidative dimerization of indoxyl, and their presence underpins the plant's traditional use as a dye source as well as its pharmacological interest.

Triterpenoids

The plant contains wrightial, a triterpenoid phytochemical, along with cycloartenone, cycloeucalenol, β-amyrin, and β-sitosterol isolated from the methanol extract of the immature seed pods. W. tinctoria pods contain alpha-amyrin, β-sitosterol, ursolic acid, and oleanolic acid. The stem bark contains β-amyrin, β-sitosterol, and lupeol. The leaves contain β-amyrin. The major component isolated from this plant is lupeol, which is widely used; lupeol and its derivatives are useful topically as an anti-inflammatory agent and in epidermal regeneration, in maintaining skin texture and integrity of the skin.

Sterols

Four uncommon sterols, desmosterol, clerosterol, 24-methylene-25-methylcholesterol, and 24-dehydropollinastanol, were isolated and identified in addition to several more common phytosterols.

Flavonoids

Investigation of the leaves for flavonoids led to the isolation of kaempferol-3-O-rhamnoside, quercetin 3-O-sophoroside, kaempferol, and quercetin. From the alcoholic extract of the air-dried leaves, four flavonoids were isolated and characterized. Methanolic extracts from the fruits yield high levels of flavonoids and terpenes, with total flavonoid content reported at approximately 90 mg/g dry weight equivalent to rutin.

Other Isolated Compounds

The various chemical constituents isolated from various parts of the plant are reported as 3,4-seco-lup-20(29)-en-3-oic acid, lupeol, stigmasterol, campesterol, indigotin, indirubin, tryptanthrin, isatin, anthranilate, rutin, triacontanol, wrightial, cycloartenone, cycloeucalenol, β-amyrin, alpha-amyrin, β-sitosterol, and 14α-methylzymosterol.

The basic compounds found in methanolic extract of W. tinctoria (MEWT) by GC-MS analysis were β-caryophyllene (0.22%), mome inositol (12.02%), and neophytadiene (1.61%), among others. The substantial antioxidant activity of MEWT could be due to the presence of terpenes, flavonoids, vitamin E, and other reported compounds.

Seasonal Variation in Key Constituents

A study using HPTLC and HPLC revealed that concentrations of indigotin and indirubin varied seasonally, peaking from August to November. This has practical implications for the standardization and quality control of raw materials and preparations.

4. Established and Proposed Mechanisms of Action

Pharmacological investigations demonstrate that Wrightia tinctoria exhibits anti-psoriatic, anti-inflammatory, antimicrobial, hepatoprotective, antioxidant, antidiabetic, and anticancer activities. These effects are mediated through multiple mechanisms, including modulation of oxidative stress, inhibition of pro-inflammatory cytokines, suppression of microbial growth, and regulation of cellular signaling pathways.

Anti-inflammatory: Aqueous, chloroform, and methanol extracts have been proposed to inhibit kinin- and prostaglandin-like mediators. The level of inhibition was found to be less than the standard drug diclofenac. Petroleum ether and methanol extracts of the woody stem at the doses of 100, 200, and 400 mg/kg produced significant inhibition of inflammation in carrageenan- and histamine-induced rat paw oedema, which is attributed to the presence and synergistic action of flavonoids, steroids, and related phytochemicals.
Anti-psoriatic (keratinocyte modulation): Chloroform fractions significantly reduced HaCaT cell viability and induced apoptosis, and also dose-dependently downregulated IL-8 and RANTES levels in vitro. Histopathological analysis in vivo showed decreased epidermal thickness and dermal inflammation, and key psoriasis biomarkers IL-17 and IL-23 were significantly reduced.
Antioxidant: Antioxidants such as quercetin and isorhamnetin derivatives reduce lipid peroxidation, while triterpenoids stabilize hepatocyte membranes. The mechanism includes enhancement of endogenous antioxidant enzymes such as superoxide dismutase (SOD) and catalase, leading to improved hepatic protection.
Anticancer: Wrightiadione and related flavonoids isolated from Wrightia tinctoria exhibit cytotoxic activity against various cancer cell lines, including breast and lung cancer models. The mechanism involves induction of apoptosis, inhibition of angiogenesis, and modulation of signaling pathways such as NF-κB and PI3K/Akt.
Antidiabetic: W. tinctoria significantly lowered blood glucose levels (P<0.05) in animal models, while not showing a direct correlation between blood glucose and insulin levels, suggesting that its hypoglycemic effects may involve mechanisms other than direct insulin secretagogue action.
Wound healing: Latex protease from Wrightia tinctoria significantly accelerated wound healing, achieving complete epithelialization by day 9 in mice.
Antifungal (indirubin): Leaf chloroform extract showed activity at 0.5 mg/ml against Trichophyton rubrum, Epidermophyton floccosum, Aspergillus niger, and Scopulariopsis brevicaulis. The major compound identified as indirubin exhibited activity against dermatophytes including Epidermophyton floccosum (MIC = 6.25 µg/ml) and Trichophyton rubrum and T. tonsurans (MIC = 25 µg/ml).
Hepatoprotective: The triterpene fraction isolated from the stem bark of Wrightia tinctoria (containing lupeol, β-amyrin, and β-sitosterol) was assessed for hepatoprotective effect on CCl4-induced hepatotoxicity in the rat. Research showed that methanolic extracts reduced CCl4-induced liver damage, as indicated by decreased ALT and AST levels in treated rats.

5. Scientific Evidence by Area of Use

5.1 Dermatology: Psoriasis and Skin Disorders

Psoriasis is the most heavily researched area for Wrightia tinctoria. Evidence ranges from in silico modelling through in vitro and in vivo animal studies to limited clinical observations.

In Silico and Systems Pharmacology Evidence

A systems pharmacology study aimed to decipher the mechanism of action of W. tinctoria in curing psoriasis and its associated comorbidities. The work integrated pharmacology approaches including drug-likeness evaluation, oral bioavailability predictions, and network pharmacology approaches; it identified 67 compounds of W. tinctoria interacting with 238 protein targets. Another study included in silico docking of phytocompounds obtained from Wrightia tinctoria with the human psoriasin (1PSR) protein, and the results highlighted that certain active compounds exhibited strong binding affinities towards the 1PSR associated with psoriasis development. Squalene, one of the tested compounds, showed particular promise in inhibiting the target protein. These findings are exploratory and hypothesis-generating only.

In Vitro and Animal Evidence

In vitro assays using HaCaT cells assessed cell viability, apoptosis, and inflammatory markers; in vivo studies utilized an IMQ-induced psoriasis mouse model, evaluating skin lesions, histopathology, and cytokine profiles. In vivo, the fractions reduced skin inflammation, edema, and psoriasis scores; histopathological analysis showed decreased epidermal thickness and dermal inflammation; and key psoriasis biomarkers IL-17 and IL-23 were significantly reduced. Chloroform:methanol fractions from W. tinctoria demonstrated potent anti-psoriatic effects in vitro and in vivo. Anti-proliferative effects were particularly distinct at higher concentrations (200 µg/mL), with inhibition rates reaching over 85% for W. tinctoria extracts.

A 1998 study by Mitra SK et al. (published in the Indian Journal of Dermatology) evaluated the reversal of parakeratosis, a feature of psoriasis, by Wrightia tinctoria in emulsion using histological evaluation based on the mouse tail test.

Human / Clinical Evidence

Human clinical data on Wrightia tinctoria are limited in number and methodological quality. The most frequently cited clinical reference is a publication by Baktha Reddy NB: a clinical and histopathological evaluation of the effect of the Wrightia tinctoria formulation RegSoR® on psoriasis vulgaris, published in US Dermatology Review in 2007. An earlier publication by Frederich M et al. (1997, The Antiseptic) reported on the efficacy of 777 oil (Wrightia tinctoria) in the treatment of psoriasis. The original Siddha clinical study by Krishnamurthy, Kalaimani, and Veluchamy (1981) in the Journal of Research in Ayurveda and Siddha provided initial clinical documentation for vetpalai oil in psoriasis. However, the scientific development of Wrightia tinctoria as a modern therapeutic agent faces several limitations: the majority of studies are restricted to preclinical research, with limited controlled clinical trials to validate its safety and efficacy in human populations.

Evidence strength (psoriasis): Moderate preclinical evidence; limited and methodologically weak human data. No large, randomized, double-blind controlled trials have been published in major peer-reviewed databases. The body of clinical evidence consists primarily of small observational studies, case series, or uncontrolled open-label reports.

5.2 Antimicrobial Activity

Studies have investigated the antibacterial and antifungal activities of leaf and bark extracts from Wrightia tinctoria (Pala Indigo), assessing the effectiveness of various solvent extracts against a range of pathogenic bacteria and fungi. Methanol extracts from the leaves and bark exhibited significant antibacterial properties against both Gram-positive and Gram-negative bacteria; among the various extracts, the methanol extracts showed the strongest activity, particularly against Bacillus cereus and Staphylococcus aureus. Results from one study indicate that Wrightia tinctoria extracts possess significant antimicrobial properties, particularly against multidrug-resistant (MDR) bacteria.

Kannan et al. reported that methanol and ethanol extracts of Wrightia tinctoria demonstrated antibacterial activity with MIC values of 0.5 mg/ml against Staphylococcus aureus.

Evidence strength (antimicrobial): Preliminary; all available evidence is in vitro. No controlled clinical trials in humans have been conducted to validate antimicrobial efficacy.

5.3 Antidiabetic Activity

One study aimed to evaluate the antidiabetic activity of Wrightia tinctoria using an oral glucose tolerance test and blood insulin levels in the Zucker diabetic rat model; herbal extracts of W. tinctoria reduced the blood glucose level in the oral glucose tolerance test significantly compared with the control. W. tinctoria significantly lowered blood glucose levels (P<0.05), while it did not show any direct correlation between blood glucose and insulin levels; the authors concluded that the hypoglycemic effects of W. tinctoria are more complicated and may involve other possible mechanisms of action.

Evidence strength (antidiabetic): Weak; evidence is animal model only (Zucker rat). No human clinical trials are currently available to support antidiabetic use.

5.4 Hepatoprotective Activity

Ethanolic extracts of bark and leaves demonstrate hepatoprotective effects in chemically induced liver injury models. The hepatoprotective effect of the triterpene fraction isolated from the stem bark of Wrightia tinctoria (containing lupeol, β-amyrin, and β-sitosterol) was examined on CCl4-induced hepatotoxicity in the rat; CCl4 (1.5 mg/kg, i.p.) causes peroxidative degeneration of membrane lipids, and elevation of serum marker enzymes SGPT, SGOT, and ALP with a decrease in hepatic glutathione and SOD. Hepatoprotection of the triterpene fraction was compared to silymarin, a well-known standard hepatoprotectant.

Evidence strength (hepatoprotective): Preclinical only (animal models); no human data available.

5.5 Wound Healing

The wound healing activity of ethanol extract of Wrightia tinctoria bark has been studied using incision, excision, and dead space wound models to evaluate histopathological and biochemical changes of granuloma tissue. In a re-sutured incision wound model, ethanol extract showed significant breaking strength (P<0.01) compared to control.

Evidence strength (wound healing): Preclinical only; all data from animal models.

5.6 Antioxidant Activity

GC-MS analysis study identified phytochemicals and established the antioxidant potential of methanolic extract of Wrightia tinctoria, assisting in therapeutic claims regarding this species in the traditional system. The current study supports previous reports on the antioxidant activity of W. tinctoria leaves and may provide an opportunity to amalgamate claims from indigenous use with analytical confirmation. A higher antioxidant potential in a plant might be valuable in inhibiting or retarding the development of a variety of oxidative stress-related illnesses. However, further studies are required to validate the potential of bioactive compounds detected.

Evidence strength (antioxidant): In vitro laboratory evidence; no human trials.

5.7 Anticancer Activity

Wrightiadione and related flavonoids isolated from Wrightia tinctoria exhibit cytotoxic activity against various cancer cell lines, including breast and lung cancer models; the mechanism involves induction of apoptosis, inhibition of angiogenesis, and modulation of signaling pathways such as NF-κB and PI3K/Akt. Cytotoxicity assay data have been generated: the ethanol (70%) and methanol extract of W. tinctoria leaves exhibited LC50 of 471.604 µg/ml and 517.038 µg/ml, respectively, in the brine shrimp lethality bioassay, while aqueous, petroleum ether, dichloromethane, ethyl acetate, and chloroform extracts of leaves were non-toxic by this assay.

Evidence strength (anticancer): Exclusively in vitro and cell-line data. No animal tumor model or human clinical evidence is available.

5.8 Gastrointestinal Applications

W. tinctoria is noted in Ayurvedic literature as having diverse pharmacological activities such as anthelmintic, antipsoriatic, antidysenteric, and use in the treatment of piles, skin diseases, flatulence, and bilious affections, pain, and inflammation. Scientific studies validating the antidysenteric and anthelmintic effects in animal models are referenced in review literature, but robust controlled human evidence for gastrointestinal outcomes is not currently available.

6. Body Systems and Health Areas of Association

Based on the accumulated pharmacological and traditional use literature, Wrightia tinctoria is associated with the following body systems:

Integumentary (skin) system: Psoriasis, eczema, scabies, non-specific dermatitis, dandruff, scalp disorders, wound healing, first-degree burns
Gastrointestinal system: Dysentery, diarrhoea, antiulcer, anthelmintic, flatulence, bilious affections
Hepatic system: Jaundice (traditional), hepatoprotection in preclinical models
Metabolic / endocrine: Antidiabetic activity (animal model evidence)
Immunological / inflammatory: Anti-inflammatory across multiple experimental models
Infectious disease: Antibacterial, antifungal, antiviral activity (in vitro)
Reproductive system: Aphrodisiac / fertility (traditional use only)
Oral health: Toothache relief (topical application of crushed leaves)
Neoplastic: Cytotoxic activity (in vitro cell lines only)

7. Dosage Forms and Dosages Reported in Studies

Important note: The following dosages are reported as used in research studies only, and represent the parameters of those specific experimental protocols.

Anti-inflammatory (animal, stem extract): Petroleum ether and methanol extracts of the woody stem were tested at doses of 100, 200, and 400 mg/kg in carrageenan- and histamine-induced rat paw oedema models.
Hepatoprotective (animal, triterpene fraction): Pretreatment with the triterpene fraction was studied at 125, 250, and 400 mg/kg (p.o.) in rats.
Topical leaf oil (Vetpalai Thailam / 777 Oil) preparation: 10 parts of coconut oil are mixed with 1 part of leaves of Wrightia tinctoria; this mixture is kept under direct sunlight for 7–10 days, then the oil is filtered and stored in airtight containers.
Sub-chronic toxicology (animal): A 90-day repeated-dose toxicity study was performed in rats, modifying the protocol described by OECD guideline 408, with six groups consisting of six rats in each group.
In vitro antimicrobial: Leaf chloroform extract showed antifungal activity at 0.5 mg/ml against multiple dermatophytes.
Antidiabetic (animal): Antidiabetic activity was evaluated using an oral glucose tolerance test and blood insulin levels in the Zucker diabetic rat model; herbal extracts reduced blood glucose significantly compared to control.

No standardized or consensus human dosage has been established in any regulatory monograph or clinical guideline for Wrightia tinctoria preparations.

8. Safety Considerations

Animal Toxicology Studies

Vetpalai Thailam is prepared from the leaves of Wrightia tinctoria by insolation with coconut oil as the base. The adverse effect profile of Vetpalai Thailam had not been systematically addressed prior to one study, which was taken up to assess long-term toxicity in rats. There was no mortality among the six study groups. No signs of toxicity and behavioural changes were observed. The histopathological examination of vital organs did not show any change in the architecture. This study demonstrates that Vetpalai Thailam does not cause any toxicity on long-term use in rats.

The toxicological profile shows this plant to be safe and tolerable in animal studies, which substantiates its usage as traditional medicine in its crude form.

Quality and Formulation Considerations

A critical safety-adjacent finding concerns the base oil used in preparations. Research clearly concluded that the acid value of the base oil would not only worsen psoriasis but could also inactivate and convert herbal metabolites to potentially toxic elements. Due diligence is necessary in preparing AYUSH drugs where not only the quality of herbs should be considered but also the oil base. The activity of Wrightia tinctoria decreases significantly when formulated in oil with high rancidity, whereas the activity was well preserved in oil with least rancidity. This indicates that rancidity in the base oil is a significant formulation concern affecting both efficacy and safety.

Adulteration Risk

The potential for adulteration with Holarrhena antidysenterica has been widely documented in the pharmacognostical literature. Wrightia tinctoria has often been confused with Holarrhena antidysenterica, another member of the same botanical family. This confusion can lead to substitution of one species for another, which may have differing pharmacological profiles and safety implications for commercial preparations.

Limitations of the Safety Evidence Base

Various parts of the plant have been used in traditional medicine, but there is no scientific evidence it is effective or safe for treating any disease, according to the Wikipedia article drawing on available regulatory-grade evidence. There is a difference between this plant's preclinical and clinical significance, and systematic regulatory toxicology in humans remains absent. The current safety data derive primarily from animal studies following OECD guidelines, which provide a starting basis but do not constitute human safety evidence. No interactions with pharmaceutical drugs have been documented in controlled clinical studies.

Overall Evidence Assessment

The body of scientific literature on Wrightia tinctoria is dominated by in vitro studies, animal experiments, and pharmacognostical reviews. The purpose of most recent reviews is to collect and evaluate the various chemical, medicinal, and pharmacological characteristics of W. tinctoria in relation to multiple disorders using preclinical evidence, which will serve as a valuable foundation for researchers to explore its effectiveness in clinical trials further. Robust, adequately powered, randomized, double-blind controlled clinical trials in humans are lacking across all indications. The most mature area — topical use in psoriasis via leaf oil — has limited clinical documentation (uncontrolled case series and small observational reports) but constitutes the most plausible basis for continued human investigation.

References

Health Conditions

Health conditions that Wrightia tinctoria may help support.

No conditions available.

Body Systems

Body systems that Wrightia tinctoria may help support.

No body systems available.