Uncaria tomentosa is a rain forest herb with demonstrated anti-inflammatory properties. It is therefore often used for people with rheumatoid arthritis. Preliminary studies suggest that cat's claw slows tumor growth and that it enhances immunity. It is safe in the recommended doses; side effects are usually associated with possible allergic reactions to plants in the Rubiaceae family. As more and more studies are being conducted, interest in cat's claw has come to include AIDS (in conjunction with Jergon Sacha) and Lyme disease. There are a few studies suggesting that this herb is capable of such actions because it is not only a superb free-radical scavenger but also promotes the repair of DNA.