hi..thanks for your query. Cosmelite cream is a combination of hydroquinone ,steroid and retinoid.It should not be used very continuously.Prolonged use of Hydroquinone has been associated with the development of exogenous ochronosis (a persistent blue-black pigmentation).The steroid which is contained in the product also leads to a lot of steroid related side effects like thinning and atrophy of skin.Used over a period of time they suppress the melanogenesis process,and once you stop it, the come back! The retinoid also makes you more sensitive to the sun, hence possibly increases the darkening capacity .You might have suffered for all/any one of the above. you can prevent the day to day darkening of your skin, by using a broad spectrum sunscreen every 4 hourly, you will see a significant lightening of the color. YOU can use Glycolic acid face washes , Creams having Glycolic acid and Vitamin C serums on a regular basis to make your skin healthy and clear.Oral supplements having Vit C and anti oxidants can be taken daily also. U can do a few sittings of Chemical peels from a dermatologist as these help more in exfoliation and lightening.They are also safe when done properly. Hope this helps..Take care