Cat's Claw

Other Name(s):

Griffe du Chat, Liane du Pérou, Life-giving Vine of Peru, Samento, Uña de Gato, Uncaria guianensis, Uncaria tomentosa.

Overview

Cat's claw is a plant. Two species of cat's claw, Uncaria tomentosa and Uncaria guianensis, are of primary interest for use as medicine. Uncaria tomentosa is most commonly used in the U.S., and Uncaria guianensis is typically used in Europe. Medicine is made from the root and bark. Be careful not to confuse cat's claw with cat's foot.

Cat's claw is most commonly used for improving symptoms of both osteoarthritis and rheumatoid arthritis.

It is also used for various digestive system disorders including swelling and pain (inflammation) of the large intestine (diverticulitis), inflammation of the lower bowel (colitis), inflammation of the lining of the stomach (gastritis), stomach ulcers, hemorrhoids, and leaky bowel syndrome.

Some people use cat's claw for viral infections including shingles (caused by herpes zoster), cold sores (caused by herpes simplex), and AIDS (caused by human immunodeficiency virus (HIV)).

Cat's claw is also used for chronic fatigue syndrome (CFS), wound healing, parasites, Alzheimer's disease, asthma, hay fever, cancer (especially urinary tract cancer), a particular type of brain cancer called glioblastoma, gonorrhea, dysentery, birth control, bone pains, and "cleansing" the kidneys.

How does work?

Cat's claw contains chemicals that might stimulate the immune system, kill cancer cells, and fight viruses.

SLIDESHOW

What Is Rheumatoid Arthritis (RA)? Symptoms, Treatment, Diagnosis See Slideshow

Uses

Possibly Effective for...

  • Reducing pain from a kind of arthritis called osteoarthritis. Taking a specific freeze-dried cat's claw extract (Uncaria guianensis) by mouth appears to relieve knee pain related to physical activity within one week of treatment, but it does not decrease pain at rest or decrease knee swelling. Taking a specific combination supplement (Reparagen) containing cat's claw (Vincaria) and maca (RNI 249) for 8 weeks seems to reduce pain and stiffness, improve function, and reduce the need to use rescue medication as well as taking glucosamine sulfate.
  • Improving symptoms of a kind of arthritis called rheumatoid arthritis (RA) when used with regular rheumatoid arthritis medications. Taking a specific cat's claw extract (Uncaria tomentosa) that contains chemicals called pentacyclic oxindole alkaloids but is free of other chemicals called tetracyclic oxindole alkaloids appears to improve symptoms of RA somewhat. Taken by mouth in combination with sulfasalazine or hydroxychloroquine for 24 weeks, cat's claw seems to reduce the number of painful and swollen joints.

Insufficient Evidence to Rate Effectiveness for...

  • Human papilloma virus (HPV). Early research suggests that taking a specific supplement containing echinacea, andrographis, grapefruit, papaya, pau d'arco, and cat's claw three times daily for one month can reduce the recurrence of anal warts after surgical removal in people with HPV.
  • Cancer. Early research suggests that 100 mg of cat's claw extract taken three times daily for at least 8 weeks may help reduce tiredness and improve quality of life in people with terminal solid tumors.
  • Arthritis.
  • Asthma.
  • Birth control.
  • Bone pains.
  • Chicken pox.
  • Chronic fatigue syndrome (CFS).
  • Glioblastoma.
  • Gonorrhea.
  • Hay fever.
  • Hemorrhoids.
  • Human immunodeficiency virus (HIV).
  • Inflammation of the digestive tract including colitis and diverticulitis.
  • Leaky bowel syndrome.
  • Mouth or genital herpes.
  • Parasites.
  • Shingles.
  • Stomach or intestinal ulcers.
  • Wounds.
  • Other conditions.
More evidence is needed to rate cat's claw for these uses.

Side Effects

Cat's claw is POSSIBLY SAFE for most people, when taken by mouth short-term. However, it can cause headache, dizziness, and vomiting in some people.

Precautions

Pregnancy and breast-feeding: There is some concern that cat's claw is POSSIBLY UNSAFE during pregnancy when taken by mouth. Not enough is known about the safety of cat's claw during breast-feeding. Avoid using cat's claw if you are pregnant or breast-feeding.

"Auto-immune diseases" such as multiple sclerosis (MS), lupus (systemic lupus erythematosus, SLE), or other similar conditions: Cat's claw might cause the immune system to become more active. This could increase the symptoms of auto-immune diseases. If you have one of these conditions, it's best to avoid using cat's claw without consulting with your healthcare provider.

Bleeding disorders: Cat's claw might slow blood clotting. There is concern that cat's claw might increase the risk of bruising or bleeding in people with bleeding disorders.

Low blood pressure: Low blood pressure: There is some evidence that cat's claw might lower blood pressure. If your blood pressure is already too low, this might be a problem.

Leukemia: Cat's claw might worsen this condition. Don't use it if you have leukemia.

Surgery: There is a concern that cat's claw might make blood pressure control difficult during surgery. Stop taking cat's claw at least 2 weeks before a scheduled surgery.

Interactions

Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Some medications are changed and broken down by the liver. Cat's claw might decrease how quickly the liver breaks down some medications. Taking cat's claw along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking cat's claw, talk to your healthcare provider if you are taking any medications that are changed by the liver.

Some medications changed by the liver include lovastatin (Mevacor), ketoconazole (Nizoral), itraconazole (Sporanox), fexofenadine (Allegra), triazolam (Halcion), and many others.

Medications for high blood pressure (Antihypertensive drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Cat's claw seems to decrease blood pressure. Taking cat's claw along with medications for high blood pressure might cause your blood pressure to go too low.

Some medications for high blood pressure include captopril (Capoten), enalapril (Vasotec), losartan (Cozaar), valsartan (Diovan), diltiazem (Cardizem), Amlodipine (Norvasc), hydrochlorothiazide (HydroDiuril), furosemide (Lasix), and many others.

Medications for high blood pressure (Calcium channel blockers)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Cat's claw might decrease blood pressure. Taking cat's claw with medication for high blood pressure might cause your blood pressure to go too low. Don't use cat's claw if you are taking high blood pressure medications.

Some medications for high blood pressure include nifedipine (Adalat, Procardia), verapamil (Calan, Isoptin, Verelan), diltiazem (Cardizem), isradipine (DynaCirc), felodipine (Plendil), amlodipine (Norvasc), and others

Medications for HIV/AIDS (Protease Inhibitors)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down medications used for HIV/AIDS to get rid of them. Taking cat's claw might decrease how quickly the body breaks down these medications. This could increase the effects and side effects of some medications used for HIV/AIDS.

Some of these medications used for HIV/AIDS include amprenavir (Agenerase), nelfinavir (Viracept), ritonavir (Norvir), and saquinavir (Fortovase, Invirase).

Medications that decrease the immune system (Immunosuppressants)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Cat's claw might increase the immune system. By increasing the immune system, cat's claw might decrease the effectiveness of medications that decrease the immune system.

Some medications that decrease the immune system include azathioprine (Imuran), basiliximab (Simulect), cyclosporine (Neoral, Sandimmune), daclizumab (Zenapax), muromonab-CD3 (OKT3, Orthoclone OKT3), mycophenolate (CellCept), tacrolimus (FK506, Prograf), sirolimus (Rapamune), prednisone (Deltasone, Orasone), corticosteroids (glucocorticoids), and others.

Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Cat's claw might slow blood clotting. Taking cat's claw along with medications that also slow clotting might increase the chances of bruising and bleeding in some people.

Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.

Dosing

The following doses have been studied in scientific research:

BY MOUTH:

  • For osteoarthritis of the knee: 100 mg daily of a specific freeze-dried cat's claw extract.
  • For rheumatoid arthritis: 60 mg daily in three divided doses of a specific cat's claw extract that contains no chemicals called tetracyclic oxindole alkaloids. These chemicals, while found naturally in some cat's claw, work against other chemicals in cat's claw that seem to help rheumatoid arthritis.
  • For cancer: 100 mg taken three times daily of a specific cat's claw extract.

QUESTION

The term arthritis refers to stiffness in the joints. See Answer

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

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References

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