I Have A Painful Rash Near My Vaginal Area And

I have a painful rash near my vaginal area and before that I had pimples with infection near my vagina and upper thigh for which the doctor prescribed augmentin 625mg thrice a day for 5 days. The pimples are completely gone but the rash is still present even though I apply polyfax on it and keep it clean. What do I do? It's very red and painful and itchy.