Suggest Remedy To Get Rid Of Itchy, Raised Rash On Arm

I have an area on my left arm thats raised a little bit and it itches like crazy. about 5 or 6 years ago i had something similar on my right arm. the doctor said it was from using body wash. he said it was the same concept of taking a piece of sandpaper and rubbing it on my arm. Could it possibly be the same thing? What type of home product could I use to get rid of it?