I have a very red rash in the inside creases of my upper thighs burns and itches hydrocortizone helps itching and burn but not redness. ?

Rash and steroids: Hard to know the cause of the rash. However, dermal fungal infections typically prefer skin folds because of optimal heat/dampness. Hydrocortisone would tend to exacerbate fungal infections (even despite improved itching). One might want to see a physician to confirm diagnosis and set course of optimized treatment. Good luck!