SkinCeuticals Discoloration Defense Correct Serum is a daily-use dark spot corrector clinically proven to reduce the appearance of key types of skin discoloration in all skin tones, including hard-to-treat forms such as stubborn brown patches and post-acne marks. It is formulated with 3% tranexamic acid, 1% kojic acid, 5% niacinamide, and 5% HEPES. This latest-generation formula improves the appearance of skin discoloration, brightens skin, and evens skin tone in as early as 2 weeks. Discoloration Defense is a layerable, daily-use dark spot corrector clinically proven to reduce the appearance of key types of skin discoloration in all skin tones, including hard-to-treat forms such as stubborn brown patches and post-acne marks. Tranexamic Acid minimizes the recurrence of skin discoloration and stubborn brown patches with continued use, 1% Kojic Acid helps improve skin brightness, Niacinamide has been shown to help reduce the appearance of skin discoloration and 5% HEPES helps break the bonds that bind dead skin cells to the surface for even exfoliation.