IBD and bloody stool

My 13 year old cat was diagnosed with Inflammatory Bowel Disease via intestinal biopsies. For the past several years his primary symptoms were vomiting and lack of appetite. He has now started having regular diarrhea and it sometimes contains bright red blood. Is this just par for the course with IBD and at what point, do we seek veterinary intervention. He is eating and drinking fairly well.

Hello!  IBD is a chronic (lifelong) disease and can wax and wane.  Sometimes red blood may be a sign, but it can also be a sign of other things, such as worms, cancer, polyps and clotting problems, so I can't say that that's what causing it in your cats' case. What was your cat last assessed for this condition?  It sounds as though things have changed and a repeat examination and reevaluation may be the ideal way forward.