Vitiligo is an autoimmune disorder in which skic color responsible cell melanocytes destroyed due to some body internal reason. And above which part these cell desroyed, where a white spot appear. As many authentic org of vitiligo say that it is very tricky mater to anhilate vitiligo (http://www.antivitiligo.com/) completely from your body system. And as you want complete whiteness, There are two posibilities one is expantion of vitiligo in such a way that it cover all the body, and the 2nd one is such medicine which do this.
The second option is almost imposible there is no such medicine althought there is an option of cosmetice surgery like Michael Jackson, and which is very costly.
In the first case i.e complete vitiligo in this case the color of the hair above the vitilgo patches whould also change.