The white patches are likely to be due to one of two things. The first and easiest to deal with is pityriasis versicolor, which is due to a sort of fungal infection of the skin. It is otherwise quite harmless, and usually causes no other symptoms. It can cause fawn colored patches on a pale skin or pale patches against a dark skin. The treatment is simple, usually using a shampoo containing selenium sulphide that is lathered into the skin and left for 5 to 10 minutes before washing it off again. A few applications will get rid of the fungal infection, but the depigmentation can take many weeks to recover, so there is no obvious immediate improvement. The other cause of this is called vitiligo. We suspect this could be your reason on the query. This is a condition of unknown cause, but is probably an autoimmune condition. The pigment cells in the skin are absent, and so even pale skin shows white patches, and this is much more noticeable in dark skin. There are new innovative therapies now for its treatment like PUVA, Phototherapy and later on the surgical grafting. It sometimes resolves spontaneously after months or years. It is unlikely for you now. It is important to find out which of these conditions you have, because one of them is so easy to treat. We suggest you to see a skin specialist and show him or her patches so that they can advise you accordingly.