Kojic acid is a natural derivative of a fermented fungus. It comes from mushrooms and is excellent at fading hyperpigmentation and dark spots. Kojic acid is starting to replace hydroquinone in many skincare formulations. They are both effective treatments for hyperpigmentation. Melanin is a pigment that adds brown color to your skin, hair, eyes, and more. Kojic acid inhibits your body's melanin production by blocking UV-activation of tyrosinase, the enzyme responsible for the production of melanin. This means it can help lighten existing sunspots and photodamage, fade the dark marks left from acne scarring or after a pimple, creates a more consistent skin tone and even improve melasma.
Treatment with kojic acid isn't immediate. For significant improvement, you'll need to use a kojic acid cosmetic for up to three months in some cases. Studies have shown that kojic acid works well with and enhances the effects of glycolic acid.