Cat’s claw

A macskakarom az amazonasi esőerdő ajándéka

Cat’s claw (Uncaria tomentosa) grows wild in many countries of Central and South America, especially in the Amazon rainforest. The use of this woody vine dates back to the Inca civilization. Historically, cat’s claw has been used for centuries in South America to prevent and treat disease. More recently, cat’s claw has been used for a variety of health conditions:

-viral infections (such as herpes and HIV)

-Alzheimer’s disease


-osteoarthritis and rheumatoid arthritis

-supporting the immune system

-promoting kidney health

Viral diseases, including emerging and chronic viruses, are an increasing worldwide health concern. As a consequence, the discovery of new antiviral agents from plants has assumed more urgency than in the past. A number of native Amazonian medicines of plant origin – such as cat’s claw -are known to have antimicrobial and anti-inflammatory activity.

Plants from tropical rainforests represent a rich source of potential immunomodulating substances.

Uncaria tomentosa, or uña de gato (cat’s claw), is the best known of the Peruvian medicinal plants. It grows wild in the upper Amazon region of Peru and neighboring countries, and can reach several inches in diameter and 1,000 feet in height. The part used medicinally is the inner bark of the vine. Uña de gato is considered a sacred plant among the Ashaninkas and other indigenous Peruvian Amazonian tribes.

The chemical composition of uña de gato includes 17 different alkaloids, quinovic acid glycosides, tannins, flavonoids, sterol fractions, triterpenes and other compounds. The most investigated of the active constituents in uña de gato for immunomodulating and anti-inflammatory effects are pentacyclic oxindole alkaloids, which are reported to induce a yet unknown immune regulating factor. Uña de gato contains a number of oxindole alkaloids.

The pharmacological actions of cat’s claw include antioxidant properties, anti-inflammatory activity, immunomodulation, cytoprotection, antimutagenic properties, and antihypertensive effects, as well as possible prevention of cerebral ischemia.

Cat’s claw has broad therapeutic potential, including the treatment of chronic viral infections, viral and bacterial co-infections in AIDS, cancer, the prevention of radiation damage, and in inflammatory disorders.

Some conditions reportedly improved by cat’s claw include osteoarthritis, rheumatoid arthritis, prostatitis, viral illnesses and cancer, and it may also have potential as an immunomodulating adaptogen in aging.

Possible side effects: headaches, dizziness, nausea and vomiting. In recommended dosages, cat’s claw is considered non-toxic. However, due to potential immune stimulation, uña de gato should not be used in patients scheduled for organ transplants, skin grafts, during immunosuppressive therapy. Although cat’s claw may be helpful in rheumatoid arthritis, longterm use should be avoided in patients with autoimmune disorders until further information is available.

Women who are pregnant or trying to become pregnant should avoid using cat’s claw because of its past use for preventing and aborting pregnancy. It is advisable to avoid their use during lactation, and for children under three years old.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. Cat’s claw may interfere with controlling blood pressure during or after surgery.- Sources: 1. NCCAM, 2. Altern Med Rev. 2001 Dec;6(6):567-79. , photo: Hjvannes, Johannes Keplinger (U.tomentosa)