Pruritus Ani-Anal Itching Treatment?

I few months ago I started experiencing some anal itching. It started getting so intense that I would wake up frequently in the night to scratch. I went to my dermatologist (not cheap) and she said that I might have a chronic itchy anus, otherwise known as Pruritus Ani. She recommended a few ways to clean the area better and also some topical creams to use, but my condition is not getting any better.

Does anyone have any ideas how to treat Pruritus Ani and make my anus stop itching?! It's driving me CRAZY!