Had this brown mark on my arm for several months. First noticed it after wrestling, it was red for a day or two then turned brown. Thought it may have been a rash from skin rubbing together but it has been around 5 months and it looks the same. It has never itched or hurt, sometimes it looks a little dry. I've tried anti fungal cream, polysporin, and moisturizer, none of those have helped it. I'm curious to know what it is and if it is infectious.