Pregnant and experiencing itchy under breasts

I'm currently on my 26th week and starting to get heat rash under my breasts. It's so terribly itchy and dark area start to form around the rash area (most probably due to abrasion with the bra also). I used cotton bra and ensures that my clothing are thin and cooling but still the same... Is there any lotion I can apply to better the itch? I read egocort cream is safe for pregnancy but apply under breasts safe?