Dapsone is a synthetic derivative of diamino-sulfone with anti-inflammatory and anti-bacterial properties. As a structural analog of?p-aminobenzoic acid?(PABA), dapsone inhibits?dihydropteroate?synthase (DHPS), an enzyme important in?folate?synthesis, resulting in a depletion of the?folate?pool and a reduction in the amount of?thymidylate?available for DNA synthesis. Although the exact mechanism through which dapsone exerts its anti-inflammatory activity has yet to be fully elucidated, this agent interferes with the activation and oxidative damage of myeloperoxidase in neutrophils and inhibits the integrin-mediated adherence and chemotaxis of neutrophils. Dapsone’s anti-inflammatory activities may contribute to the effects seen upon topical administration.