- Una de gato
- Life-giving vine of Peru
- Hawk's claw
For Patients & Caregivers
How It Works
Cat’s claw has not been shown to be an effective treatment for cancer or AIDS.
Cat’s claw is a vine native to South America, the bark of which has been used in traditional medicine to treat various conditions such as gastric and inflammatory disorders.It is marketed as a dietary supplement to treat viral infections, Alzheimer’s disease, cancer, arthritis, diverticulitis, peptic ulcers, colitis, gastritis, hemorrhoids, parasites, and leaky bowel syndrome.
In laboratory experiments, compounds found in cat’s claw stimulated the activity of specific immune cells known as phagocytes and T-helper cells. Cat’s claw may also be able to slow some of the processes that cause inflammation, enhance DNA repair, and may reduce certain chemotherapy side effects. However, most of these effects are observed in lab studies, with only a few small studies in humans reported. A cat’s claw extract was shown to stimulate survival of pediatric leukemic cells, which suggests that this herb may not be safe for all cancers.
To treat arthritis
A small study using a highly purified extract of a particular chemical makeup suggested modest benefit in patients with active rheumatoid arthritis, but larger well-designed studies are needed to confirm such effects.
To reduce cancer-treatment side effects
Small studies suggests that Cat’s claw may protect against abnormally low counts of white blood cells in patients receiving certain cancer treatments, and improve the quality of life in those with advanced cancer.
To treat cancer
Cat’s claw inhibits the growth of certain cancer cells in the labs. Human data are lacking.
To treat gastrointestinal disorders
Laboratory studies suggest that cat’s claw may reduce inflammation. This has not been studied in humans.
To treat HIV and AIDS
Laboratory studies suggest that cat’s claw can stimulate the activity of specific immune cells. Human studies are needed.
Do Not Take If
- You are taking warfarin or other blood thinners: Cat’s claw may increase the risk of bruising and bleeding. Clinical relevance is not known.
- You are taking drugs that are substrates of Cytochrome P450 3A4, CYP2J2, UGT1A3, UGT1A9, ABCB1, and SLCO1B1, and PXR: Cat’s claw can affect the metabolism of drugs that are substrates of these enzymes. Clinical relevance is not known.
- You are taking antiretroviral drugs: Case reports have shown that cat’s claw increases the serum concentrations of atazanavir, ritonavir and saquinavir, and can therefore, increase their side effects.
For Healthcare Professionals
Cat’s claw is a vine native to South America, the bark of which has been used in traditional medicine to treat various conditions such as gastric and inflammatory disorders (1). It is marketed as a dietary supplement to treat viral infections, Alzheimer’s disease, cancer, arthritis, diverticulitis, peptic ulcers, colitis, gastritis, hemorrhoids, parasites, and leaky bowel syndrome. In vitro studies show that constituents of this plant enhance phagocytosis, display immunomodulatory properties, alleviate inflammation, and possess antiviral and antimutagenic activities (1) (2) (3) (4) (5) (6). A cat’s claw extract was also shown to modulate DNA repair in human skin (7).
Cat’s claw also was shown to exert anticancer effects against several cancer cell lines (8) (9) (10) (11), and anti-neoplastic effects in a breast tumor model (12). It was also reported to stimulate healthy hematopoietic tissue cells and reduce side effects, such as neutropenia, associated with chemotherapy (13).
These observations were reported in cancer patients as well. In a study of breast cancer patients, cat’s claw reduced adverse effects due to chemotherapy (15), and improved the quality of life in patients with advanced cancer (32). However, a cat’s claw extract was shown to stimulate survival of pediatric leukemic cells (16), which suggests that this herb may not be safe for all cancers.
Mechanism of Action
The oxindole alkaloids have immunostimulating properties in vitro, increasing phagocytotic activity and synthesis of WBCs (5) and enhancing T-helper cell function (2). Inhibition of TNF-alpha production (3) (4) has been linked to observed anti-inflammatory activities. Mitraphylline isolated from cat’s claw was also identified as possessing anti-inflammatory effects by inhibiting the release of interleukins 1α, 1β, 4, 17, and TNF-α (21).
In other studies, acqueous extracts of cat’s claw were shown to enhance DNA repair after chemical-induced damage (22). Protection against oxidative DNA damage following UVB exposure may occur via enhanced base excision repair and inherent antioxidant effects (23). The biphasic manner in which cat’s claw modulates anxiety, initially inducing and then reversing the effect after long-term administration, is attributed to the presence of alkaloids and flavonols (18).
The quinovic acid glycoside purified fraction of cat’s claw was shown to inhibit the growth of human bladder cancer cell lines by inducing apoptosis through modulation of NF-κB (20). Cat’s claw also inhibited lactate dehydrogenase-A, an enzyme that is highly expressed in malignant and treatment-resistant tumors with poor clinical outcomes (24). In vivo studies demonstrated antineoplastic effects against breast tumors due to modulation of oxidative stress and synergy among constituents with antioxidant properties, rather than alkaloid activity (12).
GI complaints: nausea, diarrhea, stomach discomfort (25)
Acute renal failure: In a patient with systemic lupus erythematosus (SLE) (26).
Worsening motor signs: In a 38-year-old patient with Parkinson’s disease following oral intake of cat’s claw extract, with improvement in symptoms after cessation and withdrawal (27).
Anticoagulants, antihypertensives: May increase effects of cardiovascular drugs, including increased risk of bleeding (25) (28). Clinical relevance is not known.
Cytochrome P450 substrates: Cat’s claw inhibits CYP3A4 in vitro indicating that it may increase the serum levels of drugs such as nonnucleoside reverse-transcriptase inhibitors, cyclosporine, and some benzodiazepines (29). A cat’s claw extract was found to induce CYP2J2 in vitro, along with enzymes UGT1A3, UGT1A9, ABCB1, and SLCO1B1, and activated PXR, and can therefore affect the metabolism of drugs that are substrates of these enzymes (33). But clinical relevance of these interactions is not known.
Antiretrovirals: Cat’s claw was shown to increase the serum concentrations of atazanavir, ritonavir and saquinavirn in an AIDS patient (30). Data from twenty-eight pharmacokinetic studies and case-series/case reports also indicate that cat’s claw significantly increases the levels of antiretrovirals (34).