Health Guide

Cat's claw

What is it?

Cat's Claw is an herbal medicine used to treat arthritis, viral infections, cancer, and to increase the immune system.

Other names for Cat's Claw include: Una de Gato, Hawk's claw, Garabato, and Uncaria tomentosa.

Ask your doctor, nurse, or pharmacist if you need more information about this medicine or if any information in this leaflet concerns you.

Before Using:

Tell your doctor if you

  • are taking medicine or are allergic to any medicine (prescription or over-the-counter (OTC) or dietary supplement)
  • are pregnant or plan to become pregnant while using this medicine
  • are breastfeeding
  • have an autoimmune disease (lupus, rheumatoid arthritis) or use immunosuppressant medicine because of an organ transplant
  • have any other health problems, such as high blood pressure or heart or blood vessel disease


Talk with your caregiver about how much Cat's Claw you should take. The amount depends on the strength of the medicine and the reason you are taking Cat's Claw. If you are using this medicine without instructions from your caregiver, follow the directions on the medicine bottle. Do not take more medicine or take it more often than the directions tell you to.

To store this medicine:

Keep all medicine locked up and away from children. Store medicine away from heat and direct light. Do not store your medicine in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down and not work the way it should work. Throw away medicine that is out of date or that you do not need. Never share your medicine with others.

Drug and Food Interactions:

Do not take Cat's Claw without talking to your doctor first if you are taking:

  • Blood thinning medicine (examples: warfarin (Coumadin(R)), clopidogrel (Plavix(R)), aspirin, enoxaparin (Lovenox(R)), dalteparin (Fragmin(R)))


  • Before taking Cat's Claw, tell your doctor if you are pregnant or breastfeeding
  • Should not be used by organ transplant patients or anyone with an autoimmune disease
  • Children under 3 years of age should not use Cat's Claw
  • Should not be used by skin graft patients

Side Effects:

Stop taking your medicine right away and talk to your doctor if you have any of the following side effects. Your medicine may be causing these symptoms which may mean you are allergic to it.

  • Breathing problems or tightness in your throat or chest
  • Chest pain
  • Skin hives, rash, or itchy or swollen skin

Other Side Effects:

You may have the following side effects, but this medicine may also cause other side effects. Tell your doctor if you have side effects that you think are caused by this medicine.

  • Can lower hormone levels, for example: estrogen (estradiol) and progesterone
  • One case of kidney failure has been reported
  • Constipation, diarrhea, and fever may occur during the treatment of autoimmune diseases or cancers (1)


1. Schauss A: Cat's Claw (Uncaria tomentosa). Nat Med J 1998(March); 1(2):16-19.

2. McGuffin M, Hobbs C, Upton R et al(eds): American Herbal Products Association's Botanical Safety Handbook. CRC Press, Boca Raton, FL; 1997.

3. Rodriguez H, Massey PJ, Rodriguez K et al: Inhibition of steroid hormone production by a nutrition supplement "una de gato" or "cat's claw." Biol Reprod 198; 58:208.

4. Hilepo JN, Bellucci AG, Mossey RT: Acute renal failure caused by 'cat's claw' herbal remedy in a patient with systemic lupus erythematosus. Nephron 1997; 77:361.

5. Kowalak JF & Mills EJ (Eds): Professional Guide to Complementary & Alternative Therapies. Springhouse Corp., Bethlehem Pike, PA; 2001.

Last Updated: 7/4/2018
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites.

All rights reserved