Brief Answer:
digital and proctoscopic examination of rectum.

Detailed Answer:
l. Blood in the stool means there is bleeding somewhere in your digestive tract.Bleeding that happens higher up in the digestive tract may make stool appear black and tarry,.However if blood is fresh and red in color possible cause can be hemorrhoids ( bright red blood coating the stool after a bowel movement) or Anal Fissures.
Hemorrhoids are swollen veins in the lowest part of your rectum and anus. Sometimes the walls of these blood vessels stretch so thin that the veins bulge and get irritated and bleed during a bowel moment.An anal fissure is a small cut or tear in the lining of the anus. The crack in the skin causes severe pain and some bright red bleeding during and after bowel movements. Most common cause for both these problems are severe constipation.When a person is constipated they strain a lot while passing stools hence causing erosion of mucosa layer which causes bleeding.
Investigations suggested are-
A digital rectal examination - It is an important element of a clinical examination. It is a direct examination of the rectum and nearby organs.It should be done at least by a general surgeon.


Please mention your bowel habits?
Do you feel constipated?
Do you need to strain a lot while passing bowels?

Thanks.

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