I just recently was diagnosed with IBS. I've lost over half my body weight which isn't a normal symptom of IBS. This was due to a huge lack in appetite. I've been having constant constipation, and whenever I do have a bowel movement it has a blue/green coloring. It's not the feces itself, but a mucus like coating. I've never seen anything like it and it has me extremely worried. Also, I've been to the doctor and had everything check from my mouth to my anus, and they found absolutely nothing wrong with me... What could the problem be?