I have got some white patches over both eyebrows and one side of the cheek. The one over the eyebrows itch a bit.  Few years ago I faced the same issue which then later got normal of its own. Now the same problem has happen. Earlier I hd seen a dermatologist and they confirmed that it is not vitiligo. I had taken a lot of medicines at that time from different doctors but none showed permanent results. Later I stopped taking any medicine and it became normal of its own. What can be the reason behind this problem. What measures should I take pls suggest.