Uncaria tomentosa DC.


Uncaria tomentosa DC.


No documentation.

Vernacular Name

Una de gato, Cat’s claw, Paraguayo, Garabato, Samento, Una de gavilan 


Uncaria  tomentosa is a large liana (climbing vine-like plant) that has hooked thorns which are the reason it is often called ‘cat’s claw’.  It can grow up to 30 m using the thorny hooks to support its upward growth.  The leaves grow in opposite whorls and are smooth edged and elliptic.

Origin / Habitat

U. tomentosa is native to the Amazon rainforest and is found in various tropical areas of South and Central America.  It is sometimes confused with other plants making plant identification paramount.  It requires a tropical climate to survive and other plants upon which to climb.

Chemical Constituents

Proanthocyanidins, quinovic acids, oxindole alkaloids (pteridine, isopteridine, uncarine, mitraphylline, isomitraphylline), N-oxide, rhynocophylline, carboline alkaloid, hirustine, N-oxide triterpenes, polyphenols, phytosterols (stigmasterol and campesterol) [1].

Plant Part Used

Root bark [22].

Traditional Use

In South America, U.  tomentosa has a history of use that dates back to over 2000 years.  In Peru, indigenous tribes used this herb as a treatment for rheumatic complaints and inflammation.  It was also used by various indigenous peoples to treat asthma, urinary tract infections, gastric ulcers diabetes and as an internal detoxification agent [2]. Large doses were used in Peru as a contraceptive, a practice that had unwanted side effects as large doses over extended periods of time may result in sterility.

Other uses include dysentery, gonorrhea, menstrual irregularity, wounds, gastric ulcers, dysentery, fever, bone pain, cirrhosis and diabetes [2] [3].



U.  tomentosa has a complex array of constituents. Because of this, clear mechanisms of action are still being researched. U.  tomentosa has glycosides, which reportedly reduce inflammation and edema [4].According to a study reported by the Albany Medical College in Albany, NY, "The primary mechanism for U.  tomentosa anti-inflammatory actions appears to be immunomodulation via suppression of TNFalpha synthesis " [5]. A study found the use of U.  tomentosa superior to placebo in people with osteoarthritis of the knee. Again, TNF-alpha inhibition and PGE2 production were noted as being likely responsible for the anti-inflammatory properties [6]. Other studies have noted protection against oxidative stress and inhibition of NF-kappaB activation [7]. A small human double-blind study involving 40 patients with active rheumatoid arthritis were treated with Una de gato. Patients experienced a reduction in the number of painful and swollen joints [8]. The anti-inflammatory effects of U.  tomentosa are considered to be due to the sum total of the plant’s constituents, but the sterols have demonstrated anti-inflammatory activity in animal studies.

Colon toxicity has been somewhat ignored in Western medicine. It is now becoming apparent that bowel hygiene and proper flora are essential to good health. If the colon flora is out of balance (dysbiosis) or if food is not being properly digested and assimilated, toxic metabolites and mutagens may be produced. U.  tomentosa is reported to have the ability to soothe irritated and inflamed tissues and help eliminate pathogens from the GI tract [9].

The glycosides are also reported to enhance and stimulate phagocytosis, which if true would be a key part of the immune function activity of Una de gato [10] [11]. Immune function has also been supported by a study where a U.  tomentosa water soluble extract demonstrated immune enhancement via elevation of the lymphocyte/neutrophil ratio and also, for the 5 months measured, a decrease in the decay rate of antibody titer responses to a pneumococcal vaccine [12]. Other studies have demonstrated stimulation of IL-1 and IL-6 production by rat macrophage [13].   Isopteridine, an alkaloid which has been isolated, is claimed to have immuno-stimulatory properties. Triterpenoid alkaloids and quinovic acid glycosides have been isolated and studied for antiviral activity, possibly inhibiting replications of some DNA viruses [14] [15]. One of the isolated alkaloids has been used in some AIDS patients [15].

U.  tomentosa has been investigated to determine if it has usefulness in the treatment of cancer [16]. U.  tomentosa is an anti-oxidant. Anti-oxidants reduce carcinogenic toxin buildup, which stimulates abnormal cell development. Research indicates that U.  tomentosa may be able to target mutagenic cells and inhibit their development, while not affecting the homeostasis of normal cells [10]. One study demonstrated the antiproliferative effects of bark fractions from U. tomentosa on the MCF7 human breast cancer cell line [17]. Another study evaluated the antitumor properties of U.  tomentosa in two human leukemic and one lymphoma cell line. The investigators associated these properties with selective induction of apoptosis [18].

Other potentially important components in U.  tomentosa are proanthocyanidins (PCOs) [19]. PCOs are reported to be many times more powerful than vitamin C. They may reduce capillary fragility and inhibit platelet-activating factor (PAF), along with another phytochemical, rynchophylline, which may inhibit platelet aggregation and thrombus formation. Its anti-inflammatory activity, anti-allergic (antihistaminic) activity, and edema reducing effects lead to the claim that U.  tomentosa may be beneficial in reducing cardiovascular risk factors [19].

Clinicians agree that the uses of pentacyclic alkaloids (POAs) from U.  tomentosa root bark are the health promoting constituents. Tetracyclic alkaloids (TOAs) do occur in the root bark, but should be kept to a minimum in the final product as to maximize the health benefits of U.  tomentosa as a dietary supplement [23]. Also, the total alkaloids in U.  tomentosa have demonstrated amnestic effects in mice [20].


No documentation.

Interaction and Depletions

Interaction with other Herbs

No documentation.

Interaction with Drugs

U.  tomentosa should not be used in combination with any pharmaceutical or over the counter medications (especially anticoagulant or anti-platelet medications) or in individuals with bleeding disorders.

Based on pharmacology, do not use in individuals on hyper-immunoglobulin therapy, passive vaccines and immunosuppressant therapy [10].

Precautions and Contraindications

Side effects

Should not be taken by transplant recipients [21].


Not to be used by pregnant or breastfeeding women.

Age limitation

Not to be used by children.

Adverse reaction

No documentation.

Read More

  1)  Medicinal Herbs


  1. Senatore A, et al. Phytochemical and Biological Study of Uncaria tomentosa. Boll Soc Ital Biol Sper. 1989;65(6):517-520.
  2. Taylor L. The Healing Power of Rainforest Herbs:  A Guide to Understanding and Using Herbal Medicinals. New York: Square One Publishers;2005.344.
  3. Duke JA. Medicinal Plants of Latin America. New York: Taylor and Francis; 2009.413.
  4. Aquino R, et al. Plant Metabolites. New Compounds and Anti-inflammatory Activity of Uncaria tomentosa. J Nat Prod. 1981;54(2):453-459.
  5. Sandoval M, Charbonnet RM, Okuhama NN, Roberts J, Krenova Z, Trentacosti AM, et al. Cat's claw inhibits TNFalpha production and scavenges free radicals: role in cytoprotection. Free Radic Biol Med. Jul2000;29(1):71-78.
  6. Piscoya J, Rodriguez Z, Bustamante SA, Okuhama NN, Miller MJ, Sandoval M. Efficacy and safety of freeze-dried cat's claw in osteoarthritis of the knee: mechanisms of action of the species Uncaria guianensis. Inflamm Res. Sep2001;50(9):442-448.
  7. Sandoval-Chacon M, Thompson JH, Zhang XJ, Liu X, Mannick EE, Sadowska-Krowicka H, et al. Antiinflammatory actions of cat's claw: the role of NF-kappaB. Aliment Pharmacol Ther. Dec1998;12(12):1279-1289.
  8. Mur E, Hartig F, Eibl G, Schirmer M. Randomized double blind trial of an extract from the pentacyclic alkaloid-chemotype of uncaria tomentosa for the treatment of rheumatoid arthritis. J Rheumatol. Apr2002;29(4):678-681.
  9. Sandoval-Chacon M. Antiinflammatory actions of cat's claw: the role of NF-kappaB. Aliment Pharmacol Ther. Dec1998;12(12):1279-1289.
  10. Wagner H, et al. The Alkaloids of Uncaria tomentosa and Their Phagocytosis-stimulating Action. Planta Med. 1995;5:419-423.
  11. Sheng Y, Bryngelsson C, Pero RW. Enhanced DNA Repair, Immune Function and Reduced Toxicity of C-MED-100, A Novel Aqueous Extract From Uncaria tomentosa. J Ethnopharmacol. Feb2000;69(2):115-126.
  12. Lamm S, Sheng Y, Pero RW. Persistent response to pneumococcal vaccine in individuals supplemented with a novel water soluble extract of Uncaria tomentosa, C-Med-100. Phytomedicine. Jul2001;8(4):267-274.
  13. Lemaire I, Assinewe V, Cano P, Awang DV, Arnason JT. Stimulation of interleukin-1 and -6 production in alveolar macrophages by the neotropical liana, Uncaria tomentosa (una de gato). J Ethnopharmacol. Feb1999;64(2):109-115.
  14. Jones K. Cat’s Claw: Healing Vine of Peru. Seattle:Sylvan Press;1995:48-49.
  15. Aquino R, et al. New Polyhydroxylated Triterpenes from Uncaria tomentosa. J Nat Prod. 1990;53(3): 559-564.
  16. Aquino R, et al. Plant Metabolites. Structure and in Vitro Antiviral Activity of Quinovic Acid Glycosides from Uncaria tomentosa and Guettarda platypoda. J Nat Prod. 1989;52(4):679-685.
  17. Riva L, Coradini D, Di Fronzo G, De Feo V, De Tommasi N, De Simone F, Pizza C. The antiproliferative effects of Uncaria tomentosa extracts and fractions on the growth of breast cancer cell line. Anticancer Res. Jul2001;21(4A):2457-2461.
  18. Sheng Y, Pero RW, Amiri A, Bryngelsson C. Induction of apoptosis and inhibition of proliferation in human tumor cells treated with extracts of Uncaria tomentosa. Anticancer Res. Sep1998;18(5A):3363-3368.
  19. de Matta SM, et al. Alkaloids and Procyanidins of An Uncaria sp. from Peru. Farmaco. (Sci). 1976;31(7):527-535.
  20. Mohamed AF, Matsumoto K, Tabata K, Takayama H, Kitajima M, Watanabe H. Effects of Uncaria tomentosa total alkaloid and its components on experimental amnesia in mice: elucidation using the passive avoidance test. J Pharm Pharmacol. Dec2000;52(12):1553-1561.
  21. Haginiwa J, et al.  Studies of Plants Containing Indole Alkaloids. 2. On the Alkaloids of Uncaria rhynchophylla Miq.  Yakugaku Zasshi. 1973;93(4) : 448-442.
  22. Zana ( Cat's claw). www.zana.com.pe/english/cats_claw.
  23. Reinhand K.H. Uncaria tomentosa (Wild) DC: Cat's Claw, Una De Gato, or Saventano. J altern complement Med. Apr 1999, 5 (2) : 143-51.