Most people with colon polyps do not have any symptoms. You might not know you have a polyp until your health care provider finds it during an exam of your colon. However, some people with colon polyps may have: 
Change in bowel habits. Constipation or diarrhea that lasts longer than a week may mean the presence of a larger colon polyp or cancer. However, several other conditions also can cause changes in bowel habits.
Change in stool color. Blood can show up as red streaks in your stool or make stool appear black. A change in color also may be caused by certain foods, medicines or dietary supplements.
Iron deficiency anemia. Bleeding from polyps can happen slowly over time, without visible blood in your stool. Chronic bleeding may lead to iron deficiency anemia, which can make you feel tired and short of breath.
Pain. A large colon polyp can block part of your bowel, leading to crampy abdominal pain.
Rectal bleeding. This can be a sign of colon polyps or cancer or other conditions, such as hemorrhoids or minor tears of the anus.
