Cat’s Claw, also known as Uncaria tomentosa, has been used traditionally in Peru for over 2,000 years. Alkaloids, phenols, sterols and glycosides comprise some of the naturally occurring constituents of this herb. In a 52-week, randomized, double-blind trial, cat’s claw extract promoted joint comfort. Its mechanism of action is believed to involve modulation of key immune mediators, such as prostaglandins and cytokines, and antioxidant activity. This product may be contraindicated for individuals who are taking blood-thinning or antihypertensive medications due to a potential synergistic effect.