Hemorrhoids prolapse when their blood vessels swell and extend from their location in the rectum through the anus. In the anal canal, the hemorrhoid is exposed to the trauma of passing stool, particularly hard stools associated with constipation. The trauma can cause bleeding and sometimes pain when stool passes.
The presence of
can lead to anal itchiness (pruritus ani), and occasionally the constant feeling of needing to have a bowel movement. The prolapsing hemorrhoid usually returns into the anal canal or rectum on its own or can be pushed back inside with a finger, but falls out again with the next bowel movement.