How To Treat A Bleeding Bump On The Buttocks?

my husband has had a bump about in inch from his butt crack and above his anus. It started bleeding two days ago and there has been a lot of it. he went to the doctor yesterday and the doctor had no idea what it was. the doc said to put neosporin on it and he has been taking cepro for three weeks and the doc said that will help too. i helped put the neo on it today and what i saw was a bump that had a small look like an incision. we just don't no what it could be.