Suggest Treatment For Sore Skin Under The Breast

Oh, the other day, i was very sore under my breasts where my bra line is. And geez, I looked and there are like...welts, or almost look like bites where the under part of the bra hits. I've been putting hydro-cortizone on them and the symptom is improving. However, now that I think of it, from time to time I do get smaller "spots" like this under and around my breasts. It's always worse with heat.