Cuclopiroxolamin and Purithione Zinc are two complementing anti-microbe active ingredients found in the Ducray Kelual DS Treatment Shampoo recipe. Scientific research has proven their efficacy against yeasts (Tyoe malasseza), the main cause of dandruff. Additionally included in Ducray Kelual DS Treatment Shampoo is Keluamid, the original exfoliating active ingredient that sanitizes the scalp and may have anti-dandruff properties.