Joan... I'm so glad I saw your post. I've had the very same problem. My rsd is in my left leg but I keep getting a rash on my upper chest and under my arms. The doctor can't figure it out. I was so desperate that I stopped my meds for a while but it didn't make a difference. I don't think its related to the meds. The only other thing I have wrong with me is the rsd...it has to be that. I haven't found anything that makes it go away...it just seems to do it's own thing. Hope you're finding some relief...Take care.