How Can Penis Shaft And Scrotum Rash With Itching Be Treated?

Hi, I have a red rash on the shaft of my penis and on my scrotum. It is somewhat itchy from time to time and it has been there for awhile now. I've tried using Tinactin cream for two weeks and hydrocortisone for one week. Neither thing helped me at all. What could the rash be? What can I do to get rid of it?