Cat's claw, also known as uña de gato and uncaria tomentosa, is a woody vine native to South and Central America, with a concentration in the Amazon rainforest. Cat's claw vines have been known to grow up to 100 feet (30 meters) in length. Its stem has several curved thorns that resemble the claws of a cat, which is how the plant got its name. Cat's claw bark has a long history of medicinal use and is today sold as an herbal supplement in several forms, including capsules, teas, and tinctures.
Historically, cat's claw bark has been used to treat a number of digestive complaints including ulcers and dysentery. It has also been used as a traditional remedy for fever, and as a contraceptive. Common modern uses of cat's claw bark supplements include treating arthritis, lowering blood pressure, and boosting the immune system. Other cat's claw bark benefits may include anti-tumor, anti-cancer, and antioxidant effects. Cat's claw has also been researched as possible treatment for HIV and herpes infections.
Despite its long history of use and current popularity, there are no long-term scientific studies that have proved that cat's claw bark is effective at treating any medical conditions. Individuals who use cat's claw bark should inform their doctor, as cat's claw may interact with other medications. For example, cat's claw may interact with immune system drugs, blood thinners, blood pressure medications, and some hormonal medications, including contraceptive pills. Because cat's claw can lower blood pressure, people who are scheduled for surgery should both discontinue using cat's claw and inform their doctor and anesthesiologist that they are using the herb.
Reported side effects from using cat's claw bark include nausea, diarrhea, and headaches. Because cat's claw has been traditionally used as a contraceptive, women who are trying to become pregnant are advised not to use cat's claw. Pregnant women are also advised not to use cat's claw, as it may cause a miscarriage or a premature delivery. As is true of all herbal products, there is always the risk that a user might be allergic to the herb.
Because there is a potentially poisonous plant known as "cat's claw" that grows in the south of Texas and in Mexico. It's scientific name is acacia gregii. Those who wish to use cat's claw should ensure that they are consuming the medicinal plant, uncaria tomentosa, and only purchase cat's claw that has been prepared and packaged by a reputable manufacturer.