Introduction: Acneic skin is known to have higher levels of oxidative stress and lower levels of antioxidants than healthy skin. Research suggests that lipid peroxidation contributes to inflammation and creates a favorable environment for acne-causing bacteria. Therefore, an opportunity exists for topical antioxidant treatment to help disrupt this pathogenesis. We evaluated the propensity for a serum containing 0.5% silymarin, 15% vitamin C, 0.5% ferulic acid, and 0.5% salicylic acid to prevent sebum peroxidation both ex vivo and in blemish-prone skin.