Blood in the stool

Rectal bleeding is a very common symptom, is often self limiting and not reported to doctors. Persistent rectal bleeding can indicate significant gastrointestinal disease and further evaluation may be indicated.

Blood may be seen only on the toilet paper, coating the outside of faeces, or mixed with the faeces. The appearance of the blood may suggest the rate of bleeding or the point in the bowel at which bleeding has originated. To see bright red fresh blood, altered dark brown or black blood in the stools is always abnormal. The amount or appearance of blood cannot usually in isolation be used, to reliably indicate an innocent cause.

There are many conditions that can cause bleeding in the gut ranging from ulcers to cancer and further investigation by gastroscopy and/or colonoscopy may be indicated. In cases of obscure gastrointestinal bleeding wireless capsule endoscopy "Pillcam" may be recommended.

Faecal occult blood testing, a test for very tiny amounts of blood in the faeces, is commonly performed to screen average risk individuals at increased risk of colon cancer.  It is not an appropriate test if overt bleeding occurs.