Cat’s Claw 

This fact sheet provides basic information about the herb cat’s claw—common 

names, uses, potential side effects, and resources for more information. Cat’s claw 

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. 

Common Names—cat’s claw, uña de gato 

Latin Names—Uncaria tomentosa, Uncaria guianensis 

What It Is Used For 

•	 Cat’s claw has been used for centuries in South America to prevent and 

treat disease. 

•	 It has been used for a variety of health conditions, including viral infections 

(such as herpes and HIV), Alzheimer’s disease, cancer, and arthritis. 

•	 Cat’s claw has been used to support the immune system and promote 

kidney health, as well as to prevent and abort pregnancy. 

How It Is Used 

The inner bark of cat’s claw is used to make liquid extracts, capsules, and teas. 

Preparations of cat’s claw can also be applied to the skin. 

What the Science Says 

•	 There is not enough scientific evidence to determine whether cat’s claw 

works for any health problem, including arthritis, HIV, or cancer. 

•	 Small studies in humans have shown a possible benefit of cat’s claw in 

osteoarthritis and rheumatoid arthritis, but no large trials have been done. 

In laboratory studies, cat’s claw stimulates part of the immune system, but 

it has not been proven to reduce inflammation or boost the immune system 

in humans. 

•	 The National Institute on Aging is studying how cat’s claw may affect the 

brain. Findings may point to new avenues for research in Alzheimer’s 

disease treatment. 

Side Effects and Cautions 

•	 Few side effects have been reported for cat’s claw when it is taken at 

recommended dosages. Though rare, side effects may include headaches, 

dizziness, and vomiting. 

•	 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. 
 

•	 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. 

•	 Tell your health care providers about any complementary and alternative practices you 

use. Give them a full picture of what you do to manage your health. This will help ensure 

coordinated and safe care. 

Sources 

Cat’s claw. Natural Medicines Comprehensive Database Web site. Accessed at http://www.naturaldatabase.com on 

July 5, 2007. 

Cat’s claw (Uncaria tomentosa, Uncaria guianensis). Natural Standard Database Web site. Accessed at 

http://www.naturalstandard.com on July 3, 2007. 

For More Information 

Visit the NCCAM Web site at nccam.nih.gov and view: 

•	 What’s in the Bottle? An Introduction to Dietary Supplements at nccam.nih.gov/health/bottle/ 

•	 Herbal Supplements: Consider Safety, Too at nccam.nih.gov/health/supplement-safety/ 

NCCAM Clearinghouse 

Toll-free in the U.S.: 1-888-644-6226 

TTY (for deaf and hard-of-hearing callers): 1-866-464-3615 

E-mail: info@nccam.nih.gov 

CAM on PubMed 

Web site: nccam.nih.gov/camonpubmed/ 

NIH Office of Dietary Supplements 

Web site: www.ods.od.nih.gov 

This publication is not copyrighted and is in the public domain. Duplication is encouraged. 


NCCAM has provided this material for your information. It is not intended to substitute 

for the medical expertise and advice of your primary health care provider. We encourage 

you to discuss any decisions about treatment or care with your health care provider. The 

mention of any product, service, or therapy is not an endorsement by NCCAM. 

National Institutes of Health 

♦♦♦

U.S. Department of Health and Human Services 

D334 

Created December 2006 

Updated April 2008 

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