Where is the miscolored part? The picture is very vague. Why haven't you gone to a doctor?

Have you ever heard of tinea versicolor?
Tinea versicolor is a fungus infection that commonly affects the skin of young people, especially the chest, back, and upper arms and legs. It doesn't usually affect the face, though. This fungus produces spots that are either lighter than surrounding skin or reddish-brown. There may be just a few spots or many.

Tinea versicolor is caused by a fungus that lives in the skin of almost all adults. This fungus exists in two forms, one of which causes visible spots. Factors that can cause the fungus to become more visible include high humidity and immune or hormone abnormalities.

I had this and my doctor treated it with a prescribed lotion.

It can also be treated with Selson Blue (the dandruff shampoo).
Try the dandruff shampoo for a while and see if that offers some relief. If not, see a dermatologist or a general doctor.

The picture is perfectly clear if you click it to make it larger @ Eire.

Thanks Marianne.

No problem! It was a pain for me too! If you tan (I'm sure you don't b/c you're white white white {hahaha, j/k}) it will make the spots turn white. To use Selson Blue on it (It MUST be Selson Blue, not head and shoulders or anything), let it sit on there for about 10 minutes, then rinse it off.

If the dandruff shampoo doesn't work, your doctor can prescribe you a solution to use in the shower (which smells like sulfer-rather smelly stuff), or creams, and even oral medication. The only thing with the oral medication is that they have to draw blood occasionally to check and see if it's wreaking havoc on your liver.

Lemme know how the shampoo works out! Hope it helps.