Tu Fu Ling
StarSmilax glabra Roxb.
Traditionally used for
- Digestion
- Urinary & fluids
- Menstrual & women's health
- Pain & joints
- Skin
☯ TCM Properties
Resolves Toxicity; Drains Dampness; Frees the Joints and Channels; Clears Heat-Toxin from the Skin; Promotes Urination and Drains Dampness
Traditional Chinese Uses
Tu Fu Ling (土茯苓) is the rhizome of Smilax glabra Roxb. (Smilacaceae), Rhizoma Smilacis Glabrae. It is sweet and bland and neutral, entering the Liver and Stomach channels. It resolves toxicity, drains Dampness, frees the joints and channels, clears Heat toxin from the skin, and promotes urination.
Its historical reputation rests on syphilis, for which it was the principal Chinese treatment, used both for the disease and — importantly — for the joint pain, sores and neurological sequelae caused by the mercury given to treat it. That double role explains its enduring place in formulas for chronic sores, Damp-Heat skin disease, eczema and psoriasis-type eruptions, and for Damp-Heat painful obstruction with stiff, aching joints. It is also used for Damp-Heat vaginal discharge and painful urination.
It is bland and gentle, well tolerated and suitable for long courses, which is unusual among toxin-resolving herbs. Tea is traditionally avoided while taking it, on the grounds that the tannins antagonise its action.
Western Herbalism Properties
Relationships
Full-screen graph →Click a node for details · double-click to expand it · Ctrl/⌘ + scroll or two fingers to zoom and pan.
Botanical Description
Smilax glabra (Tu Fu Ling, glabrous greenbrier) is a perennial evergreen climber in the Smilacaceae family, scrambling through shrubs and small trees by means of paired tendrils arising from the petiole bases. The slender, smooth, woody stems are unarmed (unlike many congeners), and bear alternate, leathery, ovate-elliptic to lanceolate leaves 6 to 15 centimeters long, with three to five prominent longitudinal veins and a glossy dark green upper surface paling beneath. Small greenish-white flowers are borne in axillary umbels, dioecious, with six tepals and either six stamens or a three-locular ovary. The fruits are globose berries 6 to 8 millimeters in diameter, ripening from green through red to purple-black, each containing two or three seeds. The medicinal rhizome is large, irregular, knotty, hard, and reddish-brown to brownish-yellow externally with pale pinkish flesh, harvested in summer or autumn, sliced, and dried. Native to southern China, Vietnam, Thailand, India, and the eastern Himalaya.
Active Constituents
Astilbin
Dihydroflavonol glycoside (taxifolin 3-O-rhamnoside)Concentration: roughly 0.58-4.9% of the dried rhizome across sampled material; the Chinese Pharmacopoeia sets a minimum of 0.45%
The principal marker and the compound most of the modern pharmacology rests on. It is anti-inflammatory and selectively immunosuppressive in experimental models, lowers serum urate, and is protective in models of renal and hepatic injury. Its wide natural range means potency between batches varies severalfold.
Neoastilbin, isoastilbin and neoisoastilbin
Dihydroflavonol glycosides (astilbin stereoisomers)Concentration: neoastilbin reported around 9.9 mg/g and isoastilbin around 4.8 mg/g in sampled rhizome
The three stereoisomers of astilbin present alongside it in the rhizome. They interconvert on heating, which is one reason processing changes the chemical profile of the drug, and they carry broadly similar anti-inflammatory and antihyperuricaemic activity.
Engeletin
Dihydroflavonol glycoside (aromadendrin 3-O-rhamnoside)Concentration: roughly 0.03-0.68% of the dried rhizome
The 4'-deoxy analogue of astilbin. It is anti-inflammatory in intestinal and mitochondrial injury models and contributes to the overall flavonoid activity of the decoction.
5-O-Caffeoylshikimic acid
Phenylpropanoid esterConcentration: roughly 0.11-2.69% of the dried rhizome
One of the most abundant non-flavonoid constituents, present at concentrations comparable to astilbin itself, and proposed as a supplementary quality marker for the drug.
Tannins
Hydrolysable and condensed tanninsConcentration: around 20 mg/g (about 2%) of the rhizome
A quantitatively significant fraction, and the pharmacological basis of the classical instruction to avoid tea while taking this herb. Tannins bind iron and other polyvalent metals and precipitate proteins and alkaloids in the gut lumen, which affects the absorption of co-administered iron salts and of alkaloidal drugs.
Taxifolin (dihydroquercetin)
Dihydroflavonol aglyconeConcentration: present as the aglycone of astilbin; not routinely quantified
The aglycone released from astilbin and its isomers. It is antioxidant and antibacterial in vitro and is the form most likely to reach the circulation after gut hydrolysis.
Resveratrol
StilbenoidConcentration: a minor constituent; not routinely quantified
A minor stilbene of the rhizome, proposed among the candidate quality markers. Its concentration is too low for it to explain the drug's actions.
SGM2
Mannose-binding lectin (glycoprotein)Concentration: isolated protein fraction; content of the crude drug not reported
A mannose-binding lectin isolated from the rhizome with reported in vitro antiviral activity against herpes simplex virus type 1 and respiratory syncytial virus at IC50 values of roughly 31-63 micrograms per millilitre. Being a protein it is degraded by digestion, so it is unlikely to survive an oral decoction.
Beta-sitosterol and stigmasterol
PhytosterolsConcentration: minor constituents; not routinely quantified
Common plant sterols of the lipophilic fraction, listed among the candidate quality markers but with no established role in the drug's traditional actions.
⚠ Drug Interactions
Oral iron salts (ferrous sulfate, ferrous fumarate, ferrous gluconate)
The rhizome carries around 20 mg of tannins per gram of drug. Tannins are well established to chelate non-haem iron in the gut lumen, forming insoluble complexes that are not absorbed; this is the same mechanism by which tea and coffee depress iron absorption from a meal. A 15 to 60 g daily dose of this herb therefore delivers a substantial tannin load into the same lumen as an oral iron tablet. The effect has not been quantified for this specific herb, but the chemistry and the general tannin-iron literature are consistent enough that it should be assumed rather than dismissed.
Clinical note: Separate the iron dose from the decoction by at least two to three hours. In a patient being actively treated for iron-deficiency anaemia, re-check ferritin and haemoglobin response rather than assuming the iron regimen is working.
Tea (Camellia sinensis)
The classical materia medica explicitly prohibit taking tea with Tu Fu Ling, and the prohibition has been carried forward in the modern reviews alongside cautions against alcohol and certain meats. The plausible modern reading is additive tannin: both the herb and strong tea deliver polyphenols that bind proteins, alkaloids and minerals in the gut, further reducing the absorption of co-administered iron and alkaloidal drugs. There is no controlled study of the combination.
Clinical note: Worth passing on to the patient because it is the single instruction most consistently attached to this herb in the classical literature: take the decoction away from tea, and avoid strong tea for the duration of a course.
Urate-lowering drugs (allopurinol, febuxostat, benzbromarone)
Rhizoma Smilacis Glabrae extracts lower serum uric acid in potassium oxonate and monosodium urate rodent models, acting both through xanthine oxidase inhibition and through regulation of renal urate transporters and the intestinal microbiota. Formulae built around this herb are among the most-used Chinese prescriptions for gout, and a systematic review of Tufuling-containing formulae in gout found benefit across the pooled trials. The pharmacology therefore overlaps directly with conventional urate-lowering therapy. The evidence is preclinical plus formula-level clinical work, not a dedicated interaction study.
Clinical note: Do not stop conventional urate-lowering therapy to substitute the herb. If they are used together, monitor serum urate and warn the patient that any rapid fall in urate can precipitate an acute attack; continue flare prophylaxis as you would when up-titrating allopurinol.
Smilax china (Ba Qia) and Heterosmilax japonica - documented substitutes
The rhizomes of Smilax china and of Heterosmilax species are documented commercial substitutes for Smilacis Glabrae Rhizoma, sold in several provinces under the trade name bai tu ling, white Tu Fu Ling. The root of Fagopyrum dibotrys, an unrelated Polygonaceae plant, is also reported as a look-alike. The three genuine species differ considerably in constituent profile, so an astilbin-based dose calculation does not carry across, and their traditional indications are not the same. Macroscopically, Smilax china has thorny stems and red fruit where Smilax glabra has smooth stems and blue-black fruit, and its cut surface is a darker reddish-brown, more fibrous, and lacks the sticky feel that genuine Tu Fu Ling develops when moistened. Microscopically, Heterosmilax is distinguished by amphicribral rather than collateral vascular bundles.
Clinical note: Buy on an astilbin assay meeting the Pharmacopoeia minimum of 0.45%, and reject material sold as bai tu ling or white Tu Fu Ling unless the species is confirmed. If a normally reliable prescription stops working, substitution of the Tu Fu Ling is a realistic explanation.
Immunosuppressants (ciclosporin, tacrolimus, azathioprine, methotrexate)
Astilbin, the main constituent, is repeatedly described as a selective immunosuppressant in experimental models, and extracts of the rhizome modulate T-cell responses in imiquimod-induced psoriatic inflammation in mice. No study has examined co-administration with a pharmaceutical immunosuppressant, and no clinical case of additive immunosuppression has been reported.
Clinical note: In transplant recipients or patients on established immunosuppression, treat the combination as unstudied rather than safe. Note that the tannin fraction may separately reduce absorption of an orally dosed ciclosporin or tacrolimus, so timing matters as much as pharmacodynamics.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 15–60 g | Daily | — | — | 中国药典 2020 【用法与用量】15～60g。 【性味与归经】甘、淡，平。归肝、胃经。 — Chinese Pharmacopoeia 2020, quoted verbatim; route and cautions preserved. Replaces a cleared category-filler value. |
Evidence Tier
Strong evidence · 5 studiesRecorded studies by study design, strongest design at the top. This is a study-design tier only, not a GRADE rating: it does not weigh risk of bias, consistency or precision.
Systematic review / meta-analysis
1
1 verified · 0 unverified
Randomized controlled trial
0
Other clinical trial
0
Observational / case report
0
In vitro / animal
4
3 verified · 1 unverified
Show 4 studies
- Protective effects of Rhizoma smilacis glabrae extracts on potassium oxonate- and monosodium urate-induced hyperuricemia and gout in mice
- Integrated network pharmacological analysis revealed that Smilax glabra Roxb. alleviates IMQ-induced psoriatic skin inflammation through regulating T cell immune response
- Influence of heat processing on the anti-inflammatory activity of fresh Smilax glabra based on PDE4 inhibition
- Identification of chemical constituents of Smilax glabra Roxb. and comparative study on pharmacokinetics of 12 main bioactive components in normal and hyperuricemia rats by UPLC-Q-Exactive Orbitrap-HRMS method
Other / unclassified
0
Verified: design read from PubMed for a DOI that resolves to the cited paper Unverified: taken from the study's recorded description
Clinical Studies
Multidimensional therapeutic advantages of Smilax glabra (Tufuling)-containing formulae in gout: an integrated Systematic Review and network pharmacology-based prediction
Pooled the trial literature on Chinese herbal formulae containing Tu Fu Ling in gout and combined it with network pharmacology prediction of the mechanism. The formulae, not the single herb, are what was tested, so the benefit cannot be attributed to Smilax glabra alone; the underlying trials are also mostly Chinese-language and of variable methodological quality.
Protective effects of Rhizoma smilacis glabrae extracts on potassium oxonate- and monosodium urate-induced hyperuricemia and gout in mice
Extracts of the rhizome lowered serum urate in potassium oxonate-induced hyperuricaemic mice and reduced joint inflammation in the monosodium urate model. This is the core preclinical support for the herb's now dominant modern use in gout and hyperuricaemia.
Integrated network pharmacological analysis revealed that Smilax glabra Roxb. alleviates IMQ-induced psoriatic skin inflammation through regulating T cell immune response
Smilax glabra reduced imiquimod-induced psoriasis-like skin inflammation in mice, with network pharmacology and experimental work pointing to modulation of the T-cell immune response. Supports the classical dermatological use for damp-heat skin toxin, at the animal level.
Influence of heat processing on the anti-inflammatory activity of fresh Smilax glabra based on PDE4 inhibition
Compared fresh and heat-processed Smilax glabra and found that processing changes the constituent profile and the resulting PDE4-inhibitory anti-inflammatory activity. Directly relevant to practice: the fresh rhizome, the dried sliced drug and decoction pieces prepared with heat are not chemically equivalent, and most pharmacology has been done on the dried drug.
Identification of chemical constituents of Smilax glabra Roxb. and comparative study on pharmacokinetics of 12 main bioactive components in normal and hyperuricemia rats by UPLC-Q-Exactive Orbitrap-HRMS method
Characterised the constituents of the rhizome and compared the pharmacokinetics of twelve of them in normal versus hyperuricaemic rats, finding that the disease state alters exposure. Useful groundwork for dose reasoning, though rat pharmacokinetics do not translate directly to human dosing.
Historical Texts
Ben Cao Jing Ji Zhu
Southern and Northern DynastiesBen Cao Shi Yi
Tang dynastyBen Cao Tu Jing
Song dynastyBen Cao Gang Mu
Ming dynastyDian Nan Ben Cao
Ming dynastyBen Cao Bei Yao
Qing dynastyReferences
- Hao Wu, Yu Wang, Bing Zhang, Yao-lei Li, Zhi-xin Ren, Jing-jian Huang, Zhi-qi Zhang, Zhi-jian Lin, Xiao-meng Zhang. Smilax glabra Roxb.: A Review of Its Traditional Usages, Phytochemical Constituents, Pharmacological Properties, and Clinical Applications . Drug Design, Development and Therapy (2022) [DOI]
- Mingxin Guo, Jiaqi Zeng, Zhanle Wang, Ying Shen. Advances in the chemical constituents, pharmacological activity, and clinical application of Smilacis Glabrae Rhizoma: A review and predictive analysis of quality markers (Q-markers) . Heliyon (2024) [DOI]
- Juanjuan Qiao, Gengyu Lu, Gang Wu, Hui Liu, Wanli Wang, Tianmao Zhang, Guoyong Xie, Minjian Qin. Influence of different pretreatments and drying methods on the chemical compositions and bioactivities of Smilacis Glabrae Rhizoma . Chinese Medicine (2022) [DOI]
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.
📝 Notes
Public notes from the community and your own private notes on Tu Fu Ling.
No notes yet.