The bark of the white willow tree (and related varieties) have been used since ancient times in herbal medicine. Willow extract has the ability to lower fever (antipyretic) reduce inflammation, and soothe the body (analgesic). Besides salicin (a compound related to aspirin), willow bark extract contains other salicylates, polyphenols and flavonoids that may contribute to reducing inflammatory responses that contribute to chronic diseases, along with fighting pain and lowering fevers.