Haemorrhoids are small, blood-filled swellings caused by dilated varicose veins. Initially, they are located just inside the anus (internal haemorrhoids) but can sometimes protrude (external haemorrhoids). Haemorrhoids are not dangerous.

Constipation and prolonged straining when using the toilet are thought to contribute to the formation of haemorrhoids by increasing the pressure in the veins.

Haemorrhoidsmay be present for many years but remain undetected until symptoms appear. They can cause anal bleeding and itching and also pain and discomfort. Normally, the bleeding is limited to small stains of fresh blood on the toilet paper, but more severe bleeding can sometimes be present when stools are passed.

A lump may also be felt in the anus and large haemorrhoids give a sensation that the bowel hasn't emptied completely. If you observe blood in your stools, and have the symptoms mentioned above, you should visit your doctor for a check-up. If haemorrhoids are present ,the doctor will then perform an examination to find out if there are any other possible causes of the bleeding that may be more serious. The doctor will feel the anal canal, and inspect the mucous membrane of the rectum and lower part of the large intestine using an examination tube called a proctoscope or sigmoidoscope.