Dapsone is an antibiotic in the Sulfonamide family. Oral dapsone was once a popular choice for treating moderate to severe acne, but its use declined when oral isotretinoin (Accutane) was introduced. However, the topical use of Dapsone has recently become the focus of renewed interest for acne treatment. Dapsone is widely available in oral and topical formulations. People with a history of allergic responses to Sulfonamide (Sulfa) drugs have an elevated risk of adverse events when using Dapsons.