A prolonged bleeding from rectum needs investigations and a physical examination by either a gastroenterologist or a surgeon. The common causes can be;
1) Hemorrhoids or piles
2) Anal fissure
3) Polyp rectum
5) Inflammatory bowel disease like crohn's disease
6) Growth in rectum or colon
Investigations needed to establish the cause are;
3) Barium enema
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Pain and bleeding may be indicative of anal fissure or inflamed piles. Still investigations are needed for establishing the cause.
Please feel free for your follow up questions.
Ideally you should seek an appointment with a gastroenterologist. So a certain diagnosis can be made. Gastroenterologist would do proctoscopy on the appointment, as it is a office procedure and hemorrhoids, anal fissure and rectal polyp can be diagnosed.
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