I get white rashes at night times and only on legs and later it is followed by tremendous itching and due to my nails it turn into red bloody dots and then fade into darker spots.In the first, it was on my down part of knee and now it shifted to upper part of knee. I don't understand what exactly it is as it only occur on legs and sometimes at 6 pm and sometimes in the later time and at 12 am or so. But when it occurs, I can't stop myself from itching. please do help me in solving this issue.