Uncaria tomentosa, U. guianensis

Other names: Una de Gato, Paraguaya, Garbato, Tambor hausca, Toron

Cat’s claw comes from the stem and root of two Amazonian woody vines belonging to the madder family.

Reports of successful use as a South American folk remedy for cancer prompted scientists in Germany, Austria and Italy to take a closer look at cat’s-claw.

Studies at the University of Munich in 1985 found several alkaloids with significant immuno-stimulant activity. In 1993 Italian researchers found new compounds, quinovic glycosides, which showed antiviral, antimutagenic, and antioxidant effect. An Austrian research group found several alkaloids which inhibited the growth of tumor cells in laboratory tests.

Cat’s Claw as an Herb for Medicinal Uses

cats clawThe Piura Indians used a bark decoction of cat’s claw to treat inflammation, rheumatism, gastric ulcers and tumors, and as a contraceptive. Indian groups in Colombia and Guyana use it for dysentery. Popular use of cat’s claw started in North America in the 1990s.

Contraceptive Effect: There is only anecdotal evidence of the use of Cat’s Claw in the prevention of pregnancy. In Peru, it has been used for this purpose for years in some rainforest tribes, but the amount of drug used would be considered very high. A decoction prepared from 11 to 13 pounds of the root is reduced to about 1 cup and taken at the time of menstruation. It is claimed that sterility can be maintained for 3 to 4 years after one dose (Cabieses, 1994).

In Germany and Austria, standardized cat’s claw extract has been given to cancer patients under a physician’s care to stimulate their immune system. They have also been used in cases of rheumatoid arthritis, hemorrhoids, gout, swellings, allergies, herpes infections, gastric ulcers, gastritis, inflammatory bowel conditions and AIDS. The products are registered pharmaceuticals in these countries and are available only by prescription. Controlled clinical studies are underway, but to date there is no scientific evidence that it is effective in any of the above situations.

Cat’s claw bark enhances immunity, increasing immunoglobin counts, which helps protect cells from damage. This valuable herb regulates normal blood pressure, balances cholesterol, relaxes blood vessel walls and opens up peripheral circulation. This makes it helpful for healthier skin and joints. A relaxing herb, it balances the heart rate. It supports the health of the digestive tract lining and relieves symptoms of coughs, sneezing and congestion. Cat’s claw benefits PMS, and its diuretic effect balances water in the body.

For the very young and elderly, doses must be mild to begin in order to assess tolerance; possibility of diarrhea. If combining other herbs, the amount of Cat’s Claw should be reduced.


Cat's ClawUsually cat’s-claw is used as a tincture. The tannins in the herb are released only if it is taken in an acidic medium; add a little lemon juice to a quarter-cup of water to which you add the tincture or prepare as a tea. For convenience it may be taken as a capsule.

  • Decoction: 1 teaspoon bark to 1 cup water, boil 10 to 15 minutes, allow to cool. Strain. 1 cup taken 3 times daily.
  • Alternate Decoction:Add 30 g of powder to 800 ml water; allow to simmer on the stove for 45 minutes or until there is about 500 ml liquid remaining. Allow to cool, then strain and refrigerate (Schauss, 1998).
  • Tincture: 1 to 2 ml, once or twice daily.

Culinary Uses of Cat’s Claw

Not common for culinary purposes, nor recommended.


Ashanica Indians of Peru believe that cat’s claw has life giving properties, and their folklore states that if you drink one cup of bark decoction a week it will ward off diseases, help ease bone pain, and cleanse the body. There is certainly a bit of validity to these claims. At least one researcher referred to cat’s claw as the “opener of the way” for its ability to cleanse the entire intestinal tract.

Cat’s Claw Supplement

The amount of Cat’s Claw supplements to take are not well defined although common doses in clinical trials have been 100 mg per day for osteoarthritis and 60 mg per day for rheumatoid arthritis. Some studies have used higher doses (350 mg to 500 mg per day) and daily doses as high as 10,000 mg (10 grams) have been reported among South Americans who take cat’s claw as a general tonic. As such, it is averaged out by herbalists that 500 mg is sufficient.

High doses of Cat’s Claw have not been studied for possible side effects, however. Individuals who decide to use cat’s claw should follow the directions on the package that is purchased.

Note:  Herbal cat’s claw (Uncaria guianensis or Uncaria tomentosa) should not be confused with a plant known as cat’s claw acacia (or Acacia gregii) in the United States and Mexico. Cat’s claw acacia contains chemicals that may be harmful if swallowed. Individuals who have any question about the source of the cat’s claw bark they plan to use, should not take it.


Not to be used by anyone with organ or tissue transplants (increases chance that new tissue will be recognized as an invader), autoimmune diseases, muscular sclerosis, tuberculosis, pregnancy, anyone breastfeeding. Not give to children under the age of 2. Also not to be taken by anyone using any type of hormonal medication, insulin, vaccines, or blood thinning medications.

There is one report of acute renal failure associated with Cat’s Claw ingestion in a patient with systemic lupus erythematosus. Though the patient was taking several other medications at the time, Cat’s Claw was the only agent that was discontinued. Urinalysis results gradually returned to baseline following discontinuation of the herb (Hilepo, 1997).

Because cat’s claw may stimulate the immune system, it is unclear whether the herb is safe for people with conditions affecting the immune system.

Read More about: Herbs