Arnica is a genus of perennial, herbaceous plants in the Asteraceae family that produce yellow, daisy-like flowers. Traditionally, dried flowers of arnica are used, as tincture or ointment, for topical treatment of skin bruises, contusions, and pain. A publication in Chemistry Central Journal states that Arnica contains high levels of the flavonoids quercetin, rutin, and apigenin. Flavonoids are potent antioxidants that can protect the skin from free radical damage.