Cat’s claw (U. tomentosa) is a large, woody vine that derives its name from hook-like thorns that grow along the vine and resemble the claws of a cat. Two closely related species of Uncaria are used almost interchangeably in the rainforests: U. tomentosa and U. guianensis. Both species can reach over 30 m high into the canopy. U. tomentosa has small, yellowish-white flowers, whereas U. guianensis has reddish-orange flowers and thorns that are more curved. Cat’s claw is indigenous to the Amazon rainforest and other tropical areas of South and Central America, including Peru, Colombia, Ecuador, Guyana, Trinidad, Venezuela, Suriname, Costa Rica, Guatemala, and Panama.

Uña de Gato, Cat's Claw, Uncaria tomentosa
There are other species of plants with a common name of cat’s claw (or uña de gato) in Mexico and Latin America; however, they are entirely different plants, not belonging to the Uncaria genus, or even the Rubiaceae family. Several of the Mexican uña de gato varieties have toxic properties.
TRIBAL AND HERBAL MEDICINE USES
Both South American Uncaria species are used by the indigenous peoples of the Amazon rainforest in very similar ways and have long histories of use. Cat’s claw (U. tomentosa) has been used medicinally by the Aguaruna, Asháninka, Cashibo, Conibo, and Shipibo tribes of Peru for at least 2,000 years. The Asháninka Indian tribe in central Peru has the longest recorded history of use of the plant. They are also the largest commercial source of cat’s claw from Peru today. The Asháninka use cat’s claw to treat asthma, inflammations of the urinary tract, arthritis, rheumatism, and bone pain; to recover from childbirth; as a kidney cleanser; to cure deep wounds; to control inflammation and gastric ulcers; and for cancer. Indigenous tribes in Piura use cat’s claw to treat tumors, inflammations, rheumatism, and gastric ulcers. Other Peruvian indigenous tribes use cat’s claw to treat diabetes, urinary tract cancer in women, hemorrhages, menstrual irregularity, cirrhosis, fevers, abscesses, gastritis, rheumatism, tumors, and inflammations as well as for internal cleansing and to “normalize the body.” Reportedly, cat’s claw has also been used as a contraceptive by several different tribes of Peru (but only in very large dosages). Dr. Fernando Cabieses, M.D., a noted authority on Peruvian medicinal plants, explains that the Asháninka boil 5 to 6 kg (about 12 pounds) of the root in water until it is reduced to little more than 1 cup. This decoction is then taken 1 cup daily during the period of menstruation for three consecutive months; this supposedly causes sterility for three to four years.
Cat’s claw has been used in Peru and Europe since the early 1990s as an adjunctive treatment for cancer and AIDS as well as for other diseases that target the immune system. In herbal medicine today, cat’s claw is employed around the world for many different conditions, including immune disorders, gastritis, ulcers, cancer, arthritis, rheumatism, rheumatic disorders, neuralgias, chronic inflammation of all kinds, and such viral diseases as herpes zoster (shingles). Dr. Brent Davis, D.C. has written several articles on cat’s claw and refers to it as the “opener of the way” for its ability to cleanse the entire intestinal tract and its effectiveness in treating stomach and bowel disorders (such as Crohn’s disease, leaky bowel syndrome, ulcers, gastritis, diverticulitis, and other inflammatory conditions of the bowel, stomach, and intestines). Dr. Julian Whitaker, M.D. reports using cat’s claw for its immune-stimulating effects, for cancer, to help prevent strokes and heart attacks, to reduce blood clots, and for diverticulitis and irritable bowel syndrome.
† The statements contained herein have not been evaluated by the Food and Drug Administration. The information is intended for education and information purposes only. This information is not intended to be used to diagnose, prescribe or replace proper medical care. The plant described herein is not intended to treat, cure, diagnose, mitigate or prevent any disease.