Haemorrhoids or perianal venous conditions (Q67893)

Haemorrhoids are anatomical structures of swollen veins of the rectal plexus in the walls of the anal canal and/or under the skin around the anus. The term haemorrhoids is usually related to the symptoms caused by haemorrhoids resulting in bleeding and painful swelling when they become enlarged, inflamed, thrombosed, or prolapsed. Haemorrhoids are classified according to the degree of prolapse, although this may not always reflect the severity of symptoms.