It is important to establish where the melanin is located so that a suitable therapy may be chosen, and to trace a prognosis of the treatment.The examination of the skin, with the help of a Wood’s Lamp, can also offer a certain degree of safety in determining the location of the melanin within the skin. Hydroquinone was for many years the chosen substance for blocking the production of melanin, and with the help of chemical exfoliation substances, such as Glycolic Acid and Retinoic Acid, was demonstrated to be a very efficient skin lightning agent. During the past decade, Hydroquinone has been gradually replaced by new chemical lightning substances, such as Kojic Acid and Phytic Acid, because of the instability of products that use hydroquinone (fast oxidation). Recently, documentation has appeared showing that hydroquinone is citotoxic and destroys the wall of the melanocytos, causing a definitive lesion, called residual achromia, and has no possible treatment. (Fig. 1,2) NEXT>>