Cat’s Claw (Uncaria tomentosa)
Kathi J. Kemper, MD, MPH Overview
The primary traditional uses of cat’s claw in Peru are as an anti-inflammatory, contraceptive and anti-cancer remedy. The research on cat’s claw in animal and in vitro studies is very preliminary;there are no controlled trials evaluating its clinical effects in humans. Products marketed as cat’s claw may include a variety of related and unrelated species with widely varying amounts of the active alkaloids or may be contaminated with other species. Herbalists recommend that cat’s claw not be used during pregnancy, lactation or in children less than three years old, patients undergoinggrafts and organ transplants, hemophiliacs, and patients receiving vaccines, sera, immune globulin, insulin or thymus extracts. Aside from mild nausea, it appears to have few side effects; there is one case report of acute renal failure in an adult with systemic lupus erythematosus who took cat’s claw.
Historical and Popular Uses
For over 2000 years, the Ashaninka Peruvian rain forest people haveused cat’s claw (U. tomentosa) as a tonic to ward off disease, a contraceptive and abortifacient, and to treat various inflammatory diseases including gastric ulcers, diarrhea and GI tumors, gonorrhea, arthritis and rheumatism, acne, diabetes, diseases of the urinary tract and cancer1,2. Sometimes cat’s claw is used in combination with other local herbs such as chuchuhuasi bark to treat arthritis.It is traditionally contraindicated in pregnancy, during lactation and for children less than three years old. To the Ashaninka, the specific species containing the pentacyclic oxindole alkaloids (U. tomentosa) has great power which can be recognized only by high-ranking healer-priests3. A related species (U. guianensis) which contains tetracyclic oxindole alkaloids has been used in South Americaas a wound healer, a sedative and to treat intestinal ailments, but is not considered as strong a medicine as U. tomentosa.
Kathi J. Kemper, MD, MPH Cat’s Claw Longwood Herbal Task Force: http://www.mcp.edu/herbal/default.htm Page 1 Revised July 29, 1999
Nowadays, cat’s claw is used as an immune stimulant and cancer remedy; it is also used to treat inflammatory conditions, eg. arthritis andatopic disorders; gastritis and other intestinal disorders; viral infections, including HIV; chemical and environmental sensitivities; chronic fatigue; fibromyalgia; and prostate problems4. Demand has risen as patients have combined cat’s claw with AZT as a treatment for HIV disease. Cat’s claw is included in some herbal combination remedies, e.g. with capsaicin in the arthritis cream, NikkenAnti-Arthritis. Some Essiac tea mixtures now contain cat’s claw in addition to the four traditional ingredients (burdock root, sheep sorrel, turkey rhubarb root and slippery elm bark)5. A European product containing cat’s claw is Krallendorn® tea or capsules.
Medicinal species: Uncaria tomentosa; some products may be contaminated with U. guianensis, which contains different alkaloids. Thereare 12 other species in Peru that are also called una de gato. Throughout the world there are 34 species of Uncaria with various medicinal properties. In Traditional Chinese Medicine, the “claws” or “hooks” of Uncaria are used as a sedative and antispasmodic remedy6. A Chinese herbal compound, Gou-teng, containing another species, Uncaria rhynchophylla, is used as a sedative, anticonvulsant andantihypertensive remedy7-9. One of its derivatives, isorhynchophylline, is a negative chronotrope in animals10. In other Asian cultures, another Uncaria species, callophylla, is used as an antihypertensive remedy11. Common names: Cat’s claw, Una De Gato, Garabato, Life-giving vine of Peru, Samento, Popokainangra, Unganangi. Another plant, Acacia gregii, which grows along the TexasMexico border,...