Hello,
Welcome to Just Answer and thanks for your question. Bleeding from the rectum can be caused by internal or external hemorrhoids, anal fissure, colon polyps, diverticulosis, ulcerative colitis, Crohn's colitis, gastric ulcer, and of course, cancer. You should see your doctor for an examination to try to determine where the bleeding is coming from. Bright red blood is most likely to come from the lower end of the digestive tract and be from hemorrhoids (internal or external). Darker, tarry blood is more likely to come from higher in the system (gastric ulcer). Ibuprofen typically causes irritation in the upper digestive system which would be seen as dark blood in the feces. Until you see your doctor, you can try to keep your stool soft with fiber from fruits, vegetables, whole grains, and lots of water. You may try adding a fiber supplement such as Metamucil, Benefiber, or others. Soft stool will make passing the feces easier and less irritating.
http://www.medicinenet.com/script/main/forum.asp?articlekey=24701
http://www.nlm.nih.gov/medlineplus/ency/article/003130.htm
Nurse Practitioner
Board Certified Nurse Practitioner, MS, RN. Private practice and hospitalist experience.