Hemorrhoids are abnormally swollen veins in the rectum and anus. They are much like varicose veins you might see on a person's legs. When bulging hemorrhoidal veins are irritated, they can cause surrounding membranes to swell, burn, itch, become very painful and bleed.

There are two kinds of hemorrhoids – internal and external:

  • The internal vessels can swell to form internal hemorrhoids. Internal hemorrhoids, unless they are severe, cannot be seen or felt, unlike external hemorrhoids.
  • Likewise, the external vessels can swell to form external hemorrhoids. External hemorrhoids can be seen around the outside of the anus and, many times, can be felt.