The appearance of skin patches that are darker that the surrounding skin color is usually caused by natural body processes, and sometimes by external causes. The term for this skin darkening is epidermal hyperpigmentation. Epidermal refers to the upper layer of the skin. Hyperpigmentation means excess color.
Obesity as well as exposure to sunlight can cause as well as aggravate hyper-pigmentation. Also certain areas of skin darkening is partly due to your genetic make-up.The flaking skin is due to the dryness of the skin in the area.
The active ingredient in skin lightening products is called hydoquinone. The maximum prescription strength is 4% hydroquinone, which contains twice the amount of active ingredient as over-the-counter bleaches.
Some hydroquinone products contain sunscreens or sunblock, so you don’t have to bother with applying a separate sun protection product.
Hydroquinone may also be combined with glycolic acid for its skin moisturizing benefits.