Hi Joni,
My husband has had a problem with the soft tissue around the rectum from the beginning of his treatments (into his 5th month). I'm not sure if you are experiencing the same effects as he, but we use diaper cream (desitin) to sooth the peeling/blistering in that area. It seems to help keep it from getting worse. He has not had any complaints of inside the rectum but I'm sure your phamacist could advise you on what may help.
Good luck and God bless,
Jeff's girl