2-Blood in the stools
When the person defecates, blood may appear as red, black, or tarry looking stools. As in vomiting, its color and shape will depend on the location of the bleeding. As a general rule, the further back the bleeding is in the path of the digestive system its color will be darker since the blood will be more coagulated. Thus, if the person observes red blood after a bowel movement or when cleaning with toilet paper, it could indicate a mild condition, such as hemorrhoids or anal fissure. On the contrary, if the stools are similar to tar, it could mean bleeding in the upper digestive tract, gastroenteritis or, being the most frequent symptom of this condition, colon cancer. Note that blood in the stools is also related to amebiasis and other infectious conditions that you may need to look after.