Azelaic acid, a naturally occurring saturated dicarboxylic acid found in wheat, rye, and barley, possesses antimicrobial activity, affects keratin production, and reduces inflammation. One of the brand name for azelaic acid is FINACEA,Gel, 15% is indicated for topical treatment of the inflammatory papules and pustules of mild to moderate rosacea. Although some reduction of erythema, which was present in patients with papules, and pustules of rosacea occurred in clinical studies, efficacy for treatment of erythema in rosacea in the absence of papules and pustules has not been evaluated. Rosacea is a common skin condition thought to be primarily an inflammatory disorder. Neutrophils, in particular, have been implicated in the inflammation associated with rosacea and mediate many of their effects through the release of reactive oxygen species. Many effective agents for rosacea, including topical azelaic acid have anti-inflammatory properties. Azelaic acid per se has multiple modes of action in rosacea, but an anti-inflammatory effect achieved by reducing reactive oxygen species appears to be the main pharmacological action. A possible mechanism of action for azelaic acid in the human epidermis includes its possibility to inhibit tyrosinase and of membrane-associated thioredoxin reductase enzymes, this enzyme is shown to regulate tyrosinase through a feedback mechanism involving electron transfer to intracellular thioredoxin, followed by a specific interaction between reduced thioredoxin and tyrosinase.