Suggest Treatment For Spreading Welts On Armpit With Splotches On Arms

I started out with one welt on my armpit...just to the side of where you would apply deodorant. It has now spread to both size and they are round....about the size of a quarter. I have a few splotches on my other arm beginning. This has been going on about 4 weeks now. i think it s getting better, just to have a terrible flare up. My mom passed away with lichen sclerosis in the vaginal area. I was told this can be hereditary. Does this disease occur on the armpit area?