You may notice, suddenly one day; that there are blood stains in the toilet bowl after you have finished passing stools. It is surely an alarming sight, and it could be likely that it may need evaluation.
In case you have passed a very hard stool, needed to strain to evacuate, or had a sharp pain at the anus during passage of stools, the blood seen could be from piles or a fissure. You may need a simple consultation and be cured.
Painless blood seen intermittently could be one of the first signs of polyps in the colon. In case there are risk factors, it is better to seek a consultation to evaluate if you need a colonoscopy.
Painful bleeding, or; blood mixed with stools, with associated mucus, pus or with pain in the abdomen is surely something not to ignore. The quicker you get evaluated for the cause the better it would be, as these are alarm signs.