On the right-hand side of a person’s bowels, blockage usually doesn’t occur until later stages.
This is because the space inside the bowel is large, the bowel wall however, is fairly thin and the material passing through is mostly liquid.
If there is bleeding inside, it usually isn’t obvious. However, a person may feel weak or tired because of severe anaemia caused by loss of blood.
On the left-hand side of a person’s bowel, the space inside the bowel is smaller and the material that passes through it is semi-solid.
A person may then feel cramp-like pain in the stomach or notice their poo is streaked or mixed with blood.