This is not worrisome and most likely it is from some tissue trauma in the lower bowel/rectum. Hemorrhoids (internal or external) are the most common cause but sometimes there are little fissures or breaks in the skin, usually caused by straining with bowel movements. If you have been constipated, it would be wise to treat that and most likely the bleeding will stop.
Prevention of hemorrhoids/constipation:
Drink lots of water, add a daily fiber supplement such as Metamucil, Citracel or Konsyl, exercise regularly (even a daily walk), and eat a diet rich in high fiber foods, whole grains, fruits and vegetables (preferably with skins). Try not to ever neglect your urge to have a bowel movement. Busy-ness often results in constipation when you put it off.
If in spite of efforts to reduce constipation the bleeding should get worse, see your doctor because rectal bleeding should not be ignored. But the colonoscopy is a good sign that nothing serious is going on in the bowel. These screenings catch early signs, long before you would notice anything. Also blood from higher in the bowel or from the stomach (as with ulcers) is often dark or black since it is older when it reaches the anus. Red blood is fresh and usually implies trauma closer to the outside - again suggesting hemorrhoids or anal fissures (small tears).
The answers in online forums are for information only and are not intended to substitute for medical advice and care. Please see your personal health care provider for further evaluation of your individual case.
Debbie Miller, RN