Uncaria tomentosa (Cat’s Claw Vine)

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This article is part of the Yaogará Ark, a living archive of Amazonian teacher plants and allied medicinal species.

Abstract

Uncaria tomentosa, commonly known as Cat’s Claw Vine (uña de gato, vilcacora), is a woody Amazonian liana deeply embedded in the ethnomedical traditions of Peru and neighboring countries. Revered for its purported anti-inflammatory and immune-supportive properties, it is widely utilized by Indigenous and mestizo communities for the management of inflammatory disorders and the enhancement of immune resilience. While modern pharmacological studies suggest the presence of bioactive compounds with immunomodulatory and anti-inflammatory effects, clinical validation remains limited. The ongoing intersection of traditional knowledge and contemporary research makes Uncaria tomentosa a significant focal point for Amazonian ethnobotany and traditional pharmacology [1][4][5].

Botanical Classification

  • Taxonomy:

    • Kingdom: Plantae
    • Phylum: Magnoliophyta
    • Class: Magnoliopsida
    • Subclass: Asteridae
    • Order: Gentianales
    • Family: Rubiaceae
    • Genus: Uncaria
    • Species: Uncaria tomentosa (Willd. ex Schult.) DC. [6][1]

  • Synonyms and vernacular names:

    • Frequently known as Cat’s Claw, Cat’s Claw Vine, uña de gato (Spanish), and vilcacora (Quechua/Polish herbal tradition) [2][1].

  • Morphology:

    • A robust woody liana, reportedly reaching up to 30 meters in height, readily identified by its curved, hook-like thorns (“claws”) used to ascend host vegetation.
    • Leaves are opposite, elliptic; young stems are green with bronze tips, becoming woody with age; older lianas can attain substantial girth (up to ca. 15 cm diameter).
    • Inflorescences bear tubular yellow flowers, typically observed in the spring and summer months [1][4].

These diagnostic features—especially the paired, claw-like hooks at the nodes—help distinguish U. tomentosa from sympatric lianas and from unrelated species that share the vernacular name “uña de gato.” Herbarium confirmation remains prudent in regions where multiple Uncaria species and unrelated “cat’s claw” taxa co-occur [2][1].

Geographical Distribution and Habitat

Uncaria tomentosa is indigenous to the Amazonian rainforests of South America, with primary occurrence documented across Peru, Bolivia, Brazil, Colombia, Ecuador, and Venezuela, and with distribution extending into parts of Central America [4][2]. Within this broad range, it inhabits humid tropical forests and is frequently encountered along forest margins, riverine corridors, and secondary growth where climbing substrates are abundant.

Ecologically, U. tomentosa behaves as a canopy-climbing vine, leveraging its recurved hooks to scale trees in search of light while maintaining a root system in shaded understory soils. It exhibits tolerance for the high humidity and seasonal precipitation typical of lowland Amazonia, and it adapts well to disturbed habitats and agroforestry matrices—traits that have facilitated its integration into smallholder cultivation systems [1][7]. Local ecological knowledge and nascent cultivation initiatives indicate that the plant can be established from seed or cuttings in areas providing partial shade, fertile soils, and ample moisture, mirroring its native microhabitats [1][7].

Ethnobotanical Context

Across the western Amazon, Indigenous peoples—including the Asháninka and Shipibo—describe Cat’s Claw as a life-giving vine valued for its versatility in managing inflammation, fevers, bone pain, and for “cleansing the blood.” Practices emphasize support of the body’s defenses and convalescence following febrile or infectious episodes [1][4]. In various communities, bark and root preparations are also turned to during viral epidemics, and more generally during recovery, reflecting a conceptualization of the plant as a tonic for resilience and balance [3][5].

Within mestizo herbalism and broader folk medicine, U. tomentosa is widely used for conditions framed as inflammatory or degenerative, including arthritis, gastritis, rheumatism, prostatitis, and post-viral recovery. The bark and root are the parts of choice, administered chiefly as infusions or decoctions; topical preparations are additionally applied to localized inflammation or minor wounds [3][2][1]. This repertoire reflects centuries of empirical use and an emphasis on systemic modulation rather than symptomatic palliation alone.

In recent decades, Cat’s Claw preparations—especially those derived from U. tomentosa—have become commercialized across North America and Europe within phytotherapeutic and integrative medicine markets. Products are typically positioned for immune and inflammatory concerns and are offered as cut and sifted bark, capsules, liquid extracts, and standardized preparations [2][3]. Notably, multiple taxa in Latin America are colloquially known as “uña de gato,” including other Uncaria species and unrelated vines; among them, U. tomentosa is the most intensively studied in modern pharmacology, and correct botanical sourcing is therefore essential for research and clinical consistency [2][1].

While ceremonial dimensions exist in certain Indigenous settings—especially where healing is conceived holistically as the alignment of physical and spiritual states—the use of Cat’s Claw is generally practical and medicinal rather than oriented toward visionary instruction. Ritual acknowledgments, offerings, or prayers may accompany harvest and preparation, highlighting reciprocal relations with the plant and its forest context [4].

Phytochemistry and Pharmacology

Uncaria tomentosa contains a diverse suite of secondary metabolites, prominently:

  • Oxindole alkaloids: both pentacyclic and tetracyclic types
  • Polyphenols, including flavonoids and tannins
  • Glycosides and related phenolic constituents [5][1][4]

Mechanisms of action proposed from in vitro and preclinical studies include:

  • Immunomodulation: Pentacyclic oxindole alkaloids have been associated with enhanced phagocytic activity and the modulation of cytokine profiles, potentially supporting immune function under certain conditions [5].
  • Anti-inflammatory effects: Multiple constituents appear to downregulate pro-inflammatory mediators, including the inhibition of TNF-α production and NF-κB activation, aligning with traditional uses for inflammatory disorders [5].
  • Antioxidant properties: Polyphenolic fractions exhibit free-radical scavenging activity that may contribute to tissue protection in inflammatory microenvironments [5].

Chemotype divergence is an important consideration: genetically distinct populations of U. tomentosa can vary in their relative proportions of pentacyclic versus tetracyclic oxindole alkaloids. Such variation may influence pharmacodynamic profiles, contributing to the inconsistent findings across studies and the variable efficacy reported anecdotally or in small clinical series [1][2]. For research standardization and clinical translation, authenticated material with characterized alkaloid profiles is recommended, ideally with traceability to the source population.

Clinical evidence remains limited and heterogeneous. While laboratory studies consistently support anti-inflammatory and immunomodulatory potential, robust human trials are sparse, often small, and sometimes methodologically constrained. As a result, major clinical guidelines have not adopted Cat’s Claw for specific indications, and authoritative sources continue to call for larger, controlled studies to establish efficacy, dosing parameters, and safety profiles across relevant patient populations [5][3]. This gap between laboratory promise and clinical certainty underscores the need for cautious interpretation and ethically designed trials that respect cultural contexts of use.

Drug interactions and safety: No major hazards are reported in ethnobotanical literature, and the plant enjoys a relatively benign reputation in traditional practice [7][1]. Nonetheless, rigorous clinical safety data remain limited. Individuals who are pregnant, who have autoimmune conditions, or who use immunomodulatory therapies should seek clinical guidance prior to use; consultation is also prudent for those on complex regimens or with chronic conditions [3][5]. As with many botanicals, product quality varies widely in the marketplace; practitioners should prioritize authenticated, contaminant-tested materials and consider chemotype documentation where pharmacological outcomes are critical.

Traditional Preparation and Use

Collection:

  • Harvest typically focuses on the bark and root, conducted during drier seasons to facilitate processing and reduce fungal load. In many communities, harvest is undertaken with explicit attention to reciprocity and restraint—taking small sections from mature vines and avoiding ring-barking to allow for regeneration and continued ecosystem function [4].
  • Field selection emphasizes vigorous plants away from pollution sources, and some practitioners prefer forest-edge vines believed to concentrate certain qualities. Such choices are often guided by embodied ecological knowledge and lineage-specific teachings.

Preparation:

  • Infusions and decoctions represent the primary preparation forms. Bark or root material is simmered for extended periods—often several hours—to extract oxindole alkaloids and polyphenols into aqueous solution. Decoctions are consumed in divided doses over days or weeks, with strength titrated to the constitution and condition of the patient [4][1].
  • Topical applications include poultices and washes for localized inflammation or minor wounds. In some traditions, combined internal and external use is favored during acute flares of rheumatic pain [3][1].

Administration patterns reflect local materia medica logic: Cat’s Claw may be used singly or in formulations with complementary plants selected for digestive comfort, liver support, or symptomatic relief. While detailed formulation practices vary, the common thread is a gradual, restorative approach consistent with the plant’s positioning as a tonic for systemic balance.

Ceremonial roles:

  • In certain Indigenous settings, preparation and dosing may be accompanied by prayers, songs, or offerings. Such acts are aimed at aligning the healer, patient, and plant “spirit” toward a shared therapeutic intention, while reaffirming obligations to the forest and community. Nonetheless, unlike classic visionary “teacher plants,” Cat’s Claw is usually positioned as a restorative medicinal rather than as a plant for visionary instruction [4].
  • Mestizo herbalists may similarly incorporate blessings or thanksgiving into clinical encounters and home-based care, reinforcing ethical relationships with the plant as a source of healing.

Conservation and Ethical Considerations

Sustainability:

  • Although Uncaria tomentosa is not currently classified as threatened, the globalization of demand has raised concerns about localized overharvesting, especially where bark removal is destructive or where supply chains are opaque [4]. Because the bark and root are primary medicinal tissues, unsustainable practices can kill plants or reduce vine fitness and habitat connectivity.
  • Sustainable harvesting protocols emphasize partial bark removal from mature vines, rotation of harvest sites, and avoidance of juvenile plants. Training harvesters in identification is also essential to prevent substitution with other “uña de gato” species and to protect non-target species [2][4].

Cultivation:

  • Integration into agroforestry systems is increasingly promoted in Peru and neighboring countries, providing shade-grown vines on living trellises and enabling periodic, regenerative bark harvests. U. tomentosa adapts well to secondary forest and mixed-crop systems provided adequate shade, humidity, and fertile soils are maintained [1][7].
  • Cultivation reduces pressure on wild populations and supports community livelihoods. Emerging germplasm banks and community seed networks aim to document chemotypes and preserve genetic diversity, supporting both conservation and pharmacological research trajectories.

Quality, traceability, and standards:

  • As chemotype variation can influence biological effects, building supply chains around authenticated, traceable plant material is critical. For research, voucher specimens and chemical profiling provide the foundation for reproducible findings. For commerce, voluntary standards and third-party verification can help ensure identity, purity, and consistent alkaloid profiles [1][2][5].

Cultural rights and benefit sharing:

  • Ethical research and commercialization should recognize Indigenous intellectual property, customary laws, and protocols guarding medicinal knowledge. Benefit-sharing frameworks can include community co-authorship, research partnerships, equitable royalties, and reinvestment in local conservation and healthcare initiatives.
  • Respect for Indigenous sovereignty and free, prior, and informed consent (FPIC) is fundamental as demand grows and as new derivatives and standardized extracts are developed for global markets [4].

Public health and integration:

  • Within pluralistic healthcare settings, Cat’s Claw is best situated in integrative models that respect traditional epistemologies while ensuring safety and coordination with biomedical care. Public-sector recognition can also help align conservation with health access—supporting local cultivation programs, practitioner training, and patient education on appropriate use [3][4].

References

  1. Uncaria tomentosa - Wikidoc. https://www.wikidoc.org/index.php/Uncaria_tomentosa
  2. Uncaria tomentosa - Wikipedia. https://en.wikipedia.org/wiki/Uncaria_tomentosa
  3. Cat’s Claw: Usefulness and Safety | NCCIH. https://www.nccih.nih.gov/health/cats-claw
  4. Herb of the Month - Uncaria Tomentosa or Cat’s Claw. NHAA. https://nhaa.org.au/herb-of-the-month-uncaria-tomentosa-or-cats-claw/
  5. Della Valle V. “Uncaria tomentosa.” PubMed. https://pubmed.ncbi.nlm.nih.gov/29050447/ (DOI:10.23736/S0392-0488.17.05712-1)
  6. Cat’s Claw Taxonomic Rank – Invasive.Org. https://www.invasive.org/browse/subinfo.cfm?sub=83632&cat=51
  7. Uncaria tomentosa Cat’s Claw PFAF Plant Database. https://pfaf.org/user/Plant.aspx?LatinName=Uncaria+tomentosa

License

CC BY-SA 4.0 – Yaogará Ark — a living ethnobotanical research archive

References and Licensing

This article is part of the Yaogará Ark Research Archive — an open ethnobotanical repository documenting sacred plants and Indigenous ecological knowledge of the Amazon.

Publisher: Yaogará Research Initiative — Fundación Camino al Sol License: Creative Commons Attribution–ShareAlike 4.0 International (CC BY-SA 4.0) Citation: Yaogará Research Initiative (2025). Uncaria tomentosa (Cat’s Claw Vine). Yaogará Ark Research Archive. https://ark.yaogara.org/plants/uncaria-tomentosa