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.1 Its mechanism of action is believed to involvemodulation of key immune mediators, such asprostaglandins and cytokines, and antioxidant activity.1-3 This product may be contraindicated for individuals who are taking blood-thinning or antihypertensive medications due to a potential synergistic effect.