I have tiny warts under my breasts. is it wise to use 5% fuxex on them? if i do use fudex do i need to cover the warts? how often should i apply?

No not indicated: You mean Efudex (fluorouracil) is ointment of 5 Fluorouracil a cancer drug, specifically indicated for superficial basal cancer, some times actinic or solar keratosis. First you should see your doctor or dermatologist to make sure it is a wart , and let him ( or her ) treat. If you want to treat by yourself use some available, over the counter ointment.