Cat's Claw (herb) (Uncaria Tornentosa)

Cat's Claw (herb) (Uncaria Tornentosa)

"Peruvian Dr.s have reported good success in treating hundreds of Cancer patients." "In addition, Cat's Claw tantalizes scientists with it's anti-cancer actions. In the laboratory, it kills cancer cells and stops them from reproducing. When given to people with cancer, it repairs DNA damage, a vital first step, in cancer protection."


Called "una de gato" in Spanish, cat's claw (Uncaria tomentosa) is a woody climbing vine with claw-shaped thorns, hence its name. It is harvested in the Amazon rainforest.

What It Might Do. Oral history passed down through generations of Peruvian Indians tells of using tea made from the bark of cat's claw root as a remedy for inflammation, arthritis, tumors, viral infections, ulcers, diabetes and intestinal disorders, and even for contraception.

Word of cat's claw and its purported benefits has spread from the rainforest to the Internet. It's now being touted to treat ailments ranging from asthma, irritable bowel syndrome and chemical sensitivities to multiple sclerosis, cancer and AIDS. Hundreds of Internet web sites attest to the herb's newfound popularity, many promoting absurd products like Cat's Claw Diet Cookies.

Claims for boosting immunity, easing arthritis and preventing cancer, however, appear to have some scientific basis. In Germany and Austria, standardized extracts of cat's claw are available by prescription to boost immunity in people with cancer and AIDS.

How It Might Work. Laboratory studies confirm that the unique alkaloids in cat's claw have the ability to stimulate immune cells. Other constituents called glycosides are believed to fight inflammation. Lab studies have also documented antioxidant activity and tumor-fighting potential. Despite anecdotal reports, however, human studies have been inconclusive.

If You Take. Be sure the label identifies the plant by its correct botanical name, U. tomentosa. There are many unrelated plants called cat's claw, some of which are toxic. The herb is available as dried root, capsules, tablets and tinctures, some standardized to alkaloid content.

Caution. Cat's claw may interact unfavorably with a wide range of medications, so consult your physician before using it. Be cautious if also taking anticoagulants, such as warfarin (Coumadin). Do not take cat's claw if you are pregnant, planning pregnancy, breastfeeding, or if you have a disease of the immune system or are HIV-positive. (Despite its use in Europe with AIDS and cancer patients, some experts fear the immune-stimulating effects might aggravate auto-immune diseases.)

EN Weighs In. Cat's claw may one day prove itself worthy of at least some of the claims being made. But clinical trials in humans are sorely needed to justify its widespread use. Moreover, its long-term safety is unknown. And the rapidly growing market for cat's claw, based more on hype than research, is threatening the sustainability of the plant and increasing the likelihood of mistdentitled plant use. For all these reasons, EN advises against using this herb right now.

Share this with your friends

This herb has claws

A rainforest antioxidant counters inflammation, infection, and cell damage that leads to cancer.
cALL IT UÑA DE GATO, Uncaria tomentosa, or just plain cat's claw: This South American vine has strands that can grow 100 feet and longer, climbing with the aid of curved thorns that resemble a feline's talons. The bark has been used for centuries to spur wound healing and treat intestinal distress, while recent research has confirmed anti-inflammatory activity that fights arthritis.

At the National University of San Marcos in Lima, Peru, researchers gave cat's claw or a placebo to 45 people with osteoarthritis; after four weeks, the herb group reported significantly less pain. Meanwhile, Austrian scientists at Innsbruck University Hospital gave 40 rheumatoid arthritis sufferers cat's claw or a placebo along with standard drugs; after six months, the herb group reported fewer painful, swollen joints.

Cat's claw boosts the number of germ-fighting white blood cells and increases levels of immune proteins interleukin-1 and -6. A Canadian study in the Journal of Ethnopharmacology referred to its "strong immunostimulant action." Some people combine cat's claw with echinacea to help support a weakened immune system.

As an antioxidant, cat's claw may help prevent the DNA damage at the root of cancer. Swedish investigators prescribed a dozen people a drug known to damage genes followed by a placebo or cat's claw; after eight weeks, the herb group showed far greater DNA repair and less DNA damage. In an Italian laboratory study, cat's claw extract reduced the proliferation of breast-cancer cells by 90 percent.

The typical dose of standardized extract is 250 to 300 milligrams twice a day. Cat's claw is nontoxic and rarely causes side effects, but pregnant or nursing women should avoid it. Anyone with immune-related conditions should consult a physician before taking cat's claw.

PHOTO (COLOR): DO CAT'S BARK?: Cat's claw could be a weapon against breast cancer.
By Michael Castleman