Haemorrhoids, or piles, caused by excessive straining during a bowel movement, are basically swollen veins in the anus accompanied by itching and sometimes sharp pain.
Haemorrhoids may be internal–that is, within the anal canal–or external, when they may be felt as little knobs or balls around the anal opening. Haemorrhoids are often the result of constipation, which also worsens those that already exist. There are plenty of treatments to relieve the symptoms of haemorrhoids.
Haemorrhoids don't require immediate medical attention. If you see bright red blood in the stool–a telltale sign–you can first try some home treatment. But inflammatory bowel disease or a bowel infection can cause haemorrhoid-like symptoms. So if you see very dark blood or your stool looks black, contact your doctor immediately, as this is often a sign of intestinal bleeding. Also see your doctor if you have significant rectal bleeding, persistent faecal incontinence or the pain suddenly intensifies.