CAT and vitiligo: [3–14] Imbalances in the oxidant/antioxidant system, such as the accumulation of hydrogen peroxide (H2 O2) and low catalase (CAT) levels have recently been demonstrated in the epidermis and blood of vitiligo patients.[15–18] Recent studies have also shown antioxidant systems to play a role in the pathogenesis of generalized vitiligo.[5, 6] Antioxidant status has also been studied in segmental and nonsegmental vitiligo.[19] However, the literature contains no information about the status of antioxidant systems in the blood of experimental vitiligo mice.