What Is The Remedy For Bumps On Labia Majora?

I have been battling with smooth bumps on my labia majora. My Doctor at first thought they were herpes so she put me on pills for that an it made the bumps worse. Next she thought itwas genital warts an she took a biopsy of a bump an it was negative. I have been seen by a dermatologist for this issue to an all I have been giving by him are stronger anti itch creams and a thick lotion. These have helped but i can only use the cream for 10 days an then wait a week an use again. They always seem to go away an then come back , sometimes worse and more painful than others. What should I do or ask for my doctor to try?