NCIt definition : The 5% gel preparation of dapsone, 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.;