Vitamin C is an effective antioxidant that brightens the skin tone and reduces the appearance of signs of aging. This formula offers a very fine L-Ascorbic Acid powder that visibly targets the appearance of uneven skin tone, dullness, and signs of aging and is formulated to be mixed with other treatments (except those containing Niacinamide or EUK 134). Directions Mix a small amount with other treatments in the palm of your hand and apply to face in the AM or the PM. Avoid contact with the eyes. A tingling sensation can be expected after application.