Tree of heaven

Other Names

AilanteAilanthusAilanthus altissima (Mill.) SwingleAilanthus altissima f. erythrocarpa (Carrière) RehderAilanthus altissima f. pendulifolia (Dippel) RehderAilanthus altissima f. rubra (H.Jaeger) GeerinckAilanthus altissima var. erythrocarpa (Carrière) RehderAilanthus altissima var. leucoxyla B.C.Ding & T.B.ChaoAilanthus altissima var. microphylla B.C.Ding & T.B.ChaoAilanthus altissima var. myriocephala B.C.Ding & T.B.ChaoAilanthus altissima var. pendulifolia (Dippel) RehderAilanthus altissima var. ramosissima B.C.Ding & T.B.ChaoAilanthus altissima var. sutchuenensis (Dode) Rehd. & WilsonAilanthus altissima var. tanakae (Hayata) Kanehira & SasakiAilanthus cacodendron (Ehrh.) Schinz & Thell.Ailanthus erythrocarpa CarrièreAilanthus esquirolii H.Lév.Ailanthus giraldii DodeAilanthus glandulosa Desf.Ailanthus japonica DippelAilanthus japonica K.KochAilanthus peregrina (Buc'hoz) F.A.BarkleyAilanthus pongelion J.F.Gmel.Ailanthus procera Salisb.Ailanthus rhodoptera F.Muell.Ailanthus rubra H.JaegerAilanthus sinensis Dum.Cours.Ailanthus sutchuenensis DodeAilanthus treeAilanthus vilmoriniana DodeAilanthus vilmoriniana var. henanensis Jian Y.Chen & L.Y.JinAilantoAlbonia peregrina Buc'hozBai chun piChinese sumacChoerospondias auriculata D.ChandraChou chunChouchunChun piChunshuCopal treeCopaltreeGod's treeGötterbaumParadise treePongelion cacodendron (Ehrh.) Farw.Pongelion glandulosum (Desf.) PierrePongelion vilmorinianum (Dode) Tiegh.Rhus ailanthoides Desf.Rhus cacodendron Ehrh.Rhus hypselodendron MönchRhus sinense EllisRhus sinensis Houtt.Rhus succedanea L.Shen shuStink treeStinking shumacStinking sumacStinktreeToxicodendron altissimum Mill.Varnish tree

Synopsis

Tree of Heaven (Ailanthus altissima): A Comprehensive Reference

1. Identity and Botanical Classification

Scientific Name and Taxonomy

Ailanthus altissima (Mill.) Swingle, commonly known as tree of heaven or ailanthus tree, is a deciduous tree in the quassia family (Simaroubaceae). The genus name Ailanthus is derived from the Ambonese word ailanto, meaning "heaven-tree" or "tree reaching for the sky." Altissima is Botanical Latin for "tallest" or "very tall." The species is also commonly called tree of heaven, a name in use since 1845.

Synonyms in older botanical literature include Ailanthus cacodendron (Ehrh.) and Ailanthus glandulosa Desf., and the tree is also commonly called smoke tree, God's tree, Chinese sumac, and sumac tree. It is known by several additional vernacular names including stinking sumac, varnish tree, and stink tree.

Natural Origin and Distribution

It is native to northeast and central China, and Taiwan. Unlike other members of the genus Ailanthus, it is found in temperate climates rather than the tropics. The tree of heaven was brought from China to the United States in the late 1700s as a horticultural specimen and shade tree. This plant was imported into Europe in 1740 and into the United States in 1784. It is now considered a noxious weed and vigorous invasive species, and one of the worst invasive plant species in Europe and North America.

Botanical Description

The tree is medium-sized, reaching heights between 17 and 27 m (60 and 90 ft) with a diameter at breast height of about 1 m (3 ft). Leaves are alternate, pinnately compound and large (50–60 cm long), bearing 13–25 leaflets each 7.5–13 cm long. The tree is dioecious — having separate male and female trees, although some trees bear both sexes — with small, yellow-green flowers borne in 20–40 cm long clusters; male flowers have a repulsive odor (hence its Chinese common name "Stinking Chun").

Medicinally Relevant Plant Parts

The roots, leaves, and bark are used in traditional Chinese medicine, primarily as an astringent. The dried trunk and root bark constitute the primary medicinal plant part used. Dried bark of Ailanthus altissima (abbreviated BAA in the scientific literature) is the part most extensively studied and used as a traditional medicine in Asia.

Official Recognition and Naming in Traditional Medicine

The dried bark of A. altissima, first recorded in Xin Xiu Ben Cao (新修本草), has been commonly utilized as a traditional herbal medicine for more than 2,000 years. BAA is known by different names, including Chunpi or Cortex Ailanthi (China), Shinju or Niwaurushi (Japan), and Ailanthi radicis cortex (Korea). Its dried bark is listed as an official drug in modern Chinese materia medica as "chun bai pi."

Common Preparations and Dosage Forms

Nearly every part of A. altissima has had various uses in Chinese traditional medicine. A tincture of the root bark was thought useful by American herbalists in the 19th century. In the scientific literature, researchers have prepared extracts using hydroalcoholic solvents: after shed-drying, bark material is ground into coarse powder, and 1 kg of ground bark macerated in 2.5 liters of hydroalcoholic solution (30% water and 70% methanol). The Eclectic herbal tradition of the 19th century recorded specific dosage guidelines: the dose of the tincture was given as from 5 to 60 drops, repeated as often as required, or from 2 to 4 times a day; specific ailanthus, 5 to 20 drops. These historical dosage recommendations carry no modern clinical validation. The main isolated compounds studied pharmacologically are alkaloids, quassinoids, phenylpropanoids, and triterpenoids.

2. Traditional and Historical Use

Traditional Chinese Medicine

The tree of heaven is mentioned in the oldest extant Chinese dictionary and listed in many Chinese medical texts for its purported curative ability. Within the oldest extant Chinese dictionary, the Erya, written in the 3rd century BC, the tree of heaven is mentioned second among a list of trees. It was mentioned again in a materia medica compiled during the Tang dynasty in 656 AD.

One of the oldest recipes, recorded in a work from 732 AD, was used for treating mental illness; it involved chopped root material, young boys' urine, and douchi. Li's Compendium [Bencao Gangmu] has 18 recipes that call for the bark.

BAA has been used extensively to treat asthma, epilepsy, spermatorrhea, bleeding, ascariasis, and ophthalmic diseases. The bark is used to treat anemia, hemorrhage, diarrhea, and spermatorrhea and is considered useful to treat epilepsy, diarrhea, asthma, and cardiac problems. In the Chinese system of medicines, it is used to treat colds and gastric problems. This plant is used to treat gastrointestinal ailments like diarrhea, dysentery, vermicide, and hemorrhage of the intestine. It is also used to cure leucorrhea, gonorrhea, cough, and gastric and intestinal complaints.

The samaras (winged seeds) are also used in modern Chinese medicine under the name feng yan cao (凤眼草), meaning "herbal phoenix eye," and are used as a hemostatic agent, for spermatorrhea, and for treating patients with blood in their feces or urine. It was clinically shown to be able to treat trichomoniasis, a vaginal infection caused by the protozoan Trichomonas vaginalis. (This clinical claim, cited from a Wikipedia-referenced source, should be interpreted with caution as the original primary study has not been independently verified.)

Traditional Use in Korea and Japan

The dried bark of Ailanthus altissima, commonly designated as "Chunpi" in Chinese, is extensively used as a common traditional medicine in China, Korea, and India. Ailanthus species (Simaroubaceae) have a history of use in traditional medicine, particularly for the treatment of dysentery; A. altissima is particularly noted as an antibacterial, anthelmintic, amoebicide, and insecticide.

European and American Eclectic Herbal Tradition

This plant was imported into Europe in 1740 and into the United States in 1784, initially presented as an ornamental species of fast growth and great adaptability to rough or sterile land, and was then widely used for road and park trees during most of the 19th century. In the West, an extract of the bark sold under the synonym A. glandulosa was sometimes used as an herbal remedy for various ailments including cancer. 19th-century American Eclectic physicians documented specific indications: specific indications and uses included cardiac palpitation and spasmodic or epileptiform muscular contraction. Bark was used in India as a powerful febrifuge, tonic, and stomachic, being used in decoction for dyspepsia.

A tincture of the root bark was thought useful by American herbalists in the 19th century; however, the tinctures were also known at the time to cause nausea, vomiting, and muscle weakness.

Traditional Uses in Other Systems

As a traditional medicine, it has long been used as an astringent and antiparasitic, as a central nervous system (CNS) depressant, and for the treatment of fever, epilepsy, asthma, infection, and gastric diseases. The leaves of A. altissima are used for the treatment of scabies and seborrhea.

3. Key Chemical Constituents and Active Compounds

Overall Phytochemical Profile

Approximately 221 chemical compounds have been characterized in A. altissima bark, including alkaloids, quassinoids, phenylpropanoids, triterpenoids, volatile oils, and other compound classes. The leaves of the plant are rich in such compounds as proteins, fatty acids, volatile oils, alkaloids, flavonoids, quassinoids, terpenylated coumarins, tetracyclic triterpenoids, and other active components.

Quassinoids — The Primary Bioactive Class

The quassinoid ailanthone is the most active constituent of BAA (dried bark of Ailanthus altissima). C₂₀ quassinoids are the most attractive compounds identified in Ailanthus altissima for their significant and diverse pharmacological and biological activities. Other identified quassinoids include ailanthinone, chaparrine, ailanthinol A, ailanthinol B, ailanthinol C, shinjulactone A, and 6α-tigloyloxychaparrinone. Active compounds isolated from phytotoxicity studies include ailanthone, ailanthinone, chaparrine, and ailanthinol B (quassinoid derivatives). The compound with greatest inhibitory activity is ailanthone.

Ailanthone (AIL) is a pentacyclic diterpene lactone renowned for its versatile medicinal properties, including antiviral, antitubercular, antimalarial, anti-inflammatory, and antitumor effects. It is considered that the bioactivity of quassinoids is based on plasma membrane NADH oxidase inhibition.

Alkaloids

A number of alkaloids with basic structures of β-carboline, canthine-6-one, canthine-6-one-3 N-oxide, and indole have been reported. These include 1-methoxycanthin-6-one, which has been identified as having limited phytotoxic activity compared with ailanthone.

Phenylpropanoids, Terpenes, and Other Compounds

Quercetin and isoquercetin are present in leaves, and ceryl alcohol has been reported in bark. The ailanthus tree contains various phytochemicals including quassin, saponin, and ailanthone, as well as the quinone irritant, 2,6-dimethoxybenzoquinone. Phytochemical investigations have reported the characterization of quassinoids, β-carboline alkaloids, triterpenoids, coumarins, phenylpropionamides, piperidine, and phenolic derivatives.

Mechanisms of Action

Numerous studies have confirmed that quassinoids have a wide range of biological activities, including antileukemic and anticancer, antiamoebal, antimalarial, insecticidal and antifeedant, antiviral, antifungal, antitubercular, and herbicidal activities. At the molecular level, several mechanisms have been established in preclinical studies:

Cell cycle arrest and apoptosis: Mechanistic studies showed that ailanthone induced G₀/G₁-phase cell cycle arrest, as indicated by decreased expression of cyclins and CDKs and increased expression of p21 and p27. Results demonstrated that ailanthone triggered DNA damage characterized by activation of the ATM/ATR pathway. Moreover, ailanthone-induced cell death was associated with apoptosis, as evidenced by an increased ratio of cells in the sub-G₁ phase and by PARP cleavage and caspase activation. Ailanthone-induced apoptosis was mitochondrion-mediated and involved the PI3K/AKT signaling pathway in Huh7 cells.
Anti-inflammatory signaling: A benzoquinone analogue isolated from the bark exhibited significant anti-inflammatory effects both in vitro and in vivo, reducing the secretion of proinflammatory factors at a concentration of 15 μM. Western blotting combined with molecular dynamics analysis indicated that inhibition of the NF-κB signaling pathway may partially explain the anti-inflammatory activity.
Smooth muscle relaxation: Concentration-dependent spasmolytic effects were observed on spontaneous and spasmogen-induced contractions in isolated rabbit jejunum, with the effect against high-K⁺-induced contractions being most potent, and a parallel rightward shift of the calcium response curve was observed.
Pro-apoptotic effects on cancer cells: Ailanthone exerts anticancer effects by modulating apoptosis-related molecules, upregulating pro-apoptotic factors and downregulating anti-apoptotic ones to inhibit proliferation and induce cancer cell death.

4. Scientific Evidence by Area of Use

Important note on evidence quality: The vast majority of the pharmacological research on Ailanthus altissima consists of in vitro (cell culture) and in vivo (animal) studies. Only a few traditional uses are associated with the reported pharmacological activities of BAA and have been confirmed by preclinical and clinical studies. There are currently no published large-scale human randomized controlled trials evaluating A. altissima preparations for any clinical indication.

4.1 Anticancer Activity

Numerous antitumor activities of ailanthone have been reported, including anti-liver cancer, anti-gastric cancer, anti-lung cancer, and anti-breast cancer activities. Ailanthone (AIT) is a quassinoid natural product isolated from Ailanthus altissima that displays multiple pharmacological properties, in particular significant antitumor effects against a variety of cancer cell lines in vitro. Potent in vivo activities have been evidenced in mice bearing hepatocellular carcinoma, non-small cell lung cancer, and castration-resistant prostate cancer.

Hepatocellular Carcinoma (HCC): While searching for natural anti-HCC components in Ailanthus altissima, researchers discovered that ailanthone had potent antineoplastic activity against HCC (Huh7 cells). The molecular mechanisms underlying the antitumor effect of ailanthone on HCC were evaluated both in vitro and in vivo. In vivo studies demonstrated that ailanthone inhibited the growth and angiogenesis of tumor xenografts without significant secondary adverse effects, indicating potential safety for treating HCC. This was a preclinical study only.

Breast Cancer: The mechanism underlying ailanthone's activity on MCF-7 (breast cancer) cells was investigated by MTT assay. Breast cancer MCF-7 cells were treated with 0.5, 1.0, 2.0, 4.0 and 8.0 µg/ml ailanthone for 24, 48 and 72 hours. The results revealed that ailanthone inhibited MCF-7 cell proliferation. Flow cytometry assay demonstrated that ailanthone induced apoptosis and G0/G1 cell cycle arrest in MCF-7 cells. This was an in vitro study only, with no human subjects.

Prostate Cancer: Recent studies have shown that ailanthone is efficacious in suppressing the growth of multiple tumors in vitro and in vivo. In 2016, research found that ailanthone could treat castration-resistant prostate cancer (CRPC). Numerous studies have highlighted its potent antitumor capabilities, demonstrating efficacy in prostate cancer through the marked downregulation of RPA1, a key player in DNA replication. These findings are all from preclinical (in vitro/animal) models; no human clinical trials for prostate cancer have been completed and published.

Further investigations revealed that quassinoids including ailanthone, ailantinol B, ailantinol C, and shinjulactone A showed moderate inhibitory activity at 1:100 molar ratio. The cytotoxicity of A. altissima against several tumor cells, including HepG2, HeLa, 786-O, A549, Jurkat, MCF-7, Hep3B, MDA-MB-231, LAPC4, A375, B16, and SGC-790, has been reported.

Evidence strength — Anticancer: Preclinical only (cell lines and animal xenograft models). No human clinical trials. Findings are promising but cannot be extrapolated to clinical use.

4.2 Antimalarial and Antiparasitic Activity

Extracts and isolated compounds from seedlings of Ailanthus altissima were assessed for antiplasmodial activity in vitro. Two quassinoids, ailanthone and 6α-tigloyloxychaparrinone, isolated from active extracts showed activity against both chloroquine-resistant and chloroquine-sensitive strains of Plasmodium falciparum in vitro. Only ailanthone demonstrated low toxicity against the Vero cell line (kidney cells from the African green monkey).

Quassinoids were shown to be the active principles responsible for the anti-malarial activity of Ailanthus altissima. The chloroform extract obtained from the stem and root bark of this plant inhibited in vitro the growth of Plasmodium falciparum and was active against P. berghei infections in mice. The anti-plasmodial activity has been mainly attributed to the presence of ailanthone.

Anthelmintic (worm) activity: Bark and leaves of Ailanthus altissima are widely used in European folk medicine to treat intestinal worm infections. A study aimed to rationalize a potential anthelmintic effect of A. altissima extract against the model organism Caenorhabditis elegans. Bioactivity-guided fractionation revealed the quassinoid ailanthone as the major active compound (IC₅₀ 2.47 μM). The extract caused severe damage to germ cells and rachis, which led to none or only poorly developed oocytes. These findings support the traditional use of A. altissima in phytotherapy to treat helminth infections and provide a base for standardization of the herbal material.

Evidence strength — Antimalarial/Antiparasitic: In vitro and animal model data. No human clinical trials. Traditional use is consistent with in vitro findings, but translation to clinical efficacy is unconfirmed.

4.3 Antiviral Activity

Two novel quassinoid glycosides, named chuglycosides J and K, together with fourteen known lignans were isolated from the samara of A. altissima. All compounds were evaluated for anti-tobacco mosaic virus activity, and chuglycosides J and K exhibited inhibitory effects against virus multiplication with IC₅₀ values of 56.21 ± 1.86 and 137.74 ± 3.57 μM, respectively.

Ailanthone is one of the typical C₂₀ quassinoids synthesized by the secondary metabolism of Ailanthus altissima, which has been proven to be a biologically active natural product with promising prospects and great potential for use as a lead structure for pesticide development. These antiviral studies have focused on plant viruses, not human pathogens, limiting their direct applicability to human medicine.

Evidence strength — Antiviral: In vitro studies primarily on plant viruses. No human clinical data.

4.4 Gastrointestinal Effects (Anti-diarrheal, Antispasmodic)

A 2019 in vitro and in vivo study was conducted to rationalize some of the traditional medicinal uses of Ailanthus altissima in gastrointestinal, respiratory, and cardiovascular systems. Concentration-dependent spasmolytic effects of the crude extract and its DCM fraction were observed on spontaneous and spasmogen-induced contractions in jejunum isolated from rabbit. Concentration-dependent protection against castor oil-induced diarrhea was also observed. This study was framed to give pharmacological proofs for antidiarrheal, antiasthmatic, hypotensive, and platelet aggregation inhibitory effects by using both in vitro and in vivo techniques.

A virtual screening and molecular docking study explored the use of dried A. altissima bark for ulcerative colitis, identifying compounds with affinity for disease-related targets including IL-1R, TLR, EGFR, TGFR, and Wnt proteins. The objective of this study was to explore the therapeutic basis of the dried bark of Ailanthus altissima for the treatment of ulcerative colitis based on Virtual Screening–Molecular Docking–Activity Evaluation technology. This represents an early-stage computational and in vitro investigation only.

Evidence strength — GI effects: Preclinical (animal and in vitro), consistent with traditional use. No human clinical trials published.

4.5 Anti-inflammatory Activity

The plant possesses phosphodiesterase inhibitory, angiotensin converting enzyme inhibitory, analgesic, anti-inflammatory, antipyretic, antioxidant, and antiasthmatic activities. Previous reported literature indicates that it also possesses pain reducing, ulcer healing, antipyretic, anticancer, COX inhibitory, and antioxidant potentials. These are reported from in vitro and animal studies, not from controlled human trials.

Research has shown that A. altissima exhibits numerous pharmacological effects, including antioxidant, antipyretic, antimicrobial, antiviral, antidiarrheal, anti-inflammatory, antihistaminic, analgesic, antiparasitic, and insect-repelling properties.

Evidence strength — Anti-inflammatory: Predominantly in vitro and preclinical animal data. No human clinical trials.

4.6 Cardiovascular and Platelet Effects

Inhibition of platelet aggregation may be due to antagonistic effect on P2Y1, P2Y12, and α₂-receptors and therefore downstream inhibition of calcium channel pathways as a potential target of Aa.Cr (crude extract). However, this is a preliminary part of experiments and further investigation is necessary to explore the mechanistic pathways linked with the identification and isolation of active compounds.

Evidence strength — Cardiovascular: Preliminary, preclinical only.

4.7 Antimicrobial and Antifungal Activity

It has been reported that A. altissima possesses antimicrobial and antifungal activities. Studies have confirmed antimicrobial properties of the plant's leaves, neuroprotective effects of its bark, and anti-inflammatory properties of its seeds, branches, and leaves.

Evidence strength — Antimicrobial: In vitro data only. No human clinical trials.

5. Body Systems and Health Areas of Association

Based on the available preclinical and traditional evidence, Ailanthus altissima is associated with the following body systems:

Gastrointestinal system: It has been utilized as a traditional herbal remedy for many ailments such as ascariasis, bleeding, diarrhea, dysentery, hemorrhoids, and other gastric and intestinal disorders.
Oncology/Cellular: Preclinical anticancer research spanning hepatocellular, gastric, lung, breast, and prostate cancer cell lines, mediated primarily through ailanthone's pro-apoptotic mechanisms.
Infectious disease/Parasitology: Traditional and in vitro antiparasitic (malaria, helminths, amoeba), antimicrobial, and antifungal applications.
Respiratory system: It has been used to treat asthma and other respiratory conditions for thousands of years.
Reproductive system: Traditional use for spermatorrhea, bleeding disorders, leucorrhea, and trichomoniasis.
Cardiovascular system: Historically used for cardiac palpitation; modern preclinical data support platelet aggregation inhibition and hypotensive effects.
Neurological system: Traditional use for epilepsy and mental illness, and preliminary neuroprotective properties noted for bark extracts in preclinical models.

6. Dosage Forms and Study-Reported Dosages

No standardized clinical dosage has been established for any indication. The following dosages have appeared in published studies and historical sources only:

19th-century Eclectic tincture (historical): The dose of the tincture was recorded as from 5 to 60 drops, repeated as often as required, or 2 to 4 times a day; specific ailanthus, 5 to 20 drops.
In vitro (cell culture) studies — ailanthone: Breast cancer MCF-7 cells were treated with 0.5, 1.0, 2.0, 4.0, and 8.0 µg/ml ailanthone for 24, 48, and 72 hours.
Anthelmintic in vitro study — extract: An A. altissima extract at 1 mg/mL irreversibly inhibited the reproduction of C. elegans L4 larvae.
Anthelmintic in vitro study — ailanthone IC₅₀: Bioactivity-guided fractionation revealed the quassinoid ailanthone as the major active compound with an IC₅₀ of 2.47 μM.
Antiplasmodial in vitro — quassinoids: Two quassinoids, ailanthone and 6α-tigloyloxychaparrinone, showed activity against both chloroquine-resistant and chloroquine-sensitive strains of Plasmodium falciparum in vitro.
Preclinical toxicology — oral dose in mice: To determine the relationship between ailanthone toxicity and dose/exposure in vivo, toxicokinetics of ailanthone were carried out after a single oral dose of 15 mg/kg. The stomach was identified as the main target organ, followed by the intestine and kidney. A dose of 2.5 mg/kg had no adverse effect on mice.
Anti-inflammatory compound in vitro: A benzoquinone analogue from the bark reduced the secretion of proinflammatory factors at a concentration of 15 μM.

Further studies are required to evaluate the efficacy and safety of BAA, and no human dosing guidelines exist that are supported by clinical trial data.

7. Safety Considerations and Interactions

Known Toxicity

Tree of Heaven contains chemicals that are toxic to humans if ingested, including quassinoids, which can cause gastrointestinal issues, headache, dizziness, and, in severe cases, heart problems. A tincture of the root bark was thought useful by American herbalists in the 19th century; however, the tinctures were also known at the time to cause nausea, vomiting, and muscle weakness.

Moreover, A. altissima also affects human health, causing allergies, dermatitis, and even myocarditis. The tree's noxious odors have been associated with nausea and headaches, and with contact dermatitis reported in both humans and sheep, which developed weakness and paralysis.

Preclinical Toxicological Findings

Toxicokinetics of ailanthone were carried out after a single oral dose of 15 mg/kg in mice. The stomach was identified as the main target organ, followed by the intestine and kidney. A dose of 2.5 mg/kg had no adverse effect on mice. This study represented the first evaluation of the systemic toxicity of ailanthone and is useful for future development.

In a brine shrimp test, leaf extract showed low toxicity at 24 hours post-exposure (LC₅₀ = 951.04 ± 28.26 μg/mL), with toxic effects increasing with exposure time and extract concentration.

Dermal and Allergic Reactions

Direct skin contact with sap may cause dermatitis in sensitive individuals. Ailanthus altissima, an invasive plant species, exhibits pharmacological properties but also some allergic effects on humans.

Cardiac Concerns

The tree is regarded as producing a sap that can cause heart inflammation (myocarditis). This concern is consistent with historical records of 19th-century tinctures causing muscle weakness and cardiac palpitation.

Limitations in Safety Data

The pharmacokinetics, toxicology, and quality control of BAA should be considered indispensable research topics. Only a few traditional uses are associated with the reported pharmacological activities of BAA and have been confirmed by preclinical and clinical studies. The absence of robust human clinical trial data means that no firm safety profile can be established for use as a human dietary supplement or medicine.

No Standardization

A comprehensive review published in the Journal of Ethnopharmacology (Volume 275, 2021, Article 114121) compiled the traditional uses, phytochemistry, and pharmacology of Ailanthus altissima bark. That review and others emphasize that no standardized quality control, pharmacokinetic profiling, or dosing guidance exists for clinical use.

Summary of Evidence

Ailanthus altissima (tree of heaven) has a rich and well-documented history of use in traditional Chinese, Korean, Indian, and Western herbal medicine spanning more than two millennia. Its phytochemistry is extensively characterized, with approximately 221 known compounds, among which quassinoids — particularly ailanthone — are recognized as the most pharmacologically active. Preclinical research supports a broad range of biological effects, including anticancer, antimalarial, anthelmintic, anti-inflammatory, antiviral, and spasmolytic activities, with much of the modern research focused on the cancer-related mechanisms of ailanthone.

However, the evidence base for human therapeutic use remains almost entirely preclinical. No large-scale, well-designed human clinical trials have been published for any indication. The plant's constituent quassinoids are associated with documented toxicity in traditional records and animal studies, and the absence of standardized preparations, pharmacokinetic data in humans, and clinical safety/efficacy assessments makes its current use as a dietary supplement or medicine poorly supported by evidence standards.

References

Health Conditions

Health conditions that Tree of heaven may help support.

No conditions available.

Body Systems

Body systems that Tree of heaven may help support.

No body systems available.