Recurrent diarrhea,bloating,dull pain at lt. abdomen,stools mixed with mucous like thingy for months. what could it be? it's on and off.

Mucus on stool: Mucus discharge occurs in up to 50% of patients with irritable bowel syndrome, with or without pain. Mucus may also be produced in response to partial obstruction, chronic constipation, rectal dysfunction, infection, & even from secretory villous tumors of the rectum. At the very least stool studies & probably a sigmoidoscopy should be considered, but a more extensive evaluation may be warranted.