Bulging blood vessels in the backside can be a pain, but you have many options for treating them.
Some women have a passing encounter with hemorrhoids during pregnancy. By midlife, many more of us have had one or more of the classic symptoms, which include rectal pain, itching, bleeding, and possibly prolapse (protrusion of hemorrhoids into the anal canal). Leakage of feces may also occur. Although hemorrhoids are rarely dangerous, they can be a painful recurrent bother. Fortunately, there's a lot we can do about them.
What are hemorrhoids?
In one sense, everyone has hemorrhoids — pillow-like clusters of veins that lie just beneath the mucous membranes lining the lowest part of the rectum and the anus. Trouble develops when these veins become swollen and distended, like varicose veins in the legs. And like varicose veins, hemorrhoids may be a byproduct of our blood vessels' constant battle against gravity to get blood back to the heart — and part of the price we pay for being upright creatures.
There are two kinds of hemorrhoids: internal ones, which occur in the lower rectum, and external ones, which develop under the skin around the anus. External hemorrhoids are the most uncomfortable, because they irritate and erode the overlying skin. The pain may be sudden and severe if a blood clot forms inside an external hemorrhoid. The clot usually dissolves but may leave excess skin (a skin tag) that itches or becomes irritated.
Internal hemorrhoids are usually painless, but they often result in bleeding, which may show up bright red on toilet paper or dripping into the toilet bowl. An internal hemorrhoid may also prolapse and extend beyond the anus, causing potential problems. For one thing, it may collect small amounts of mucus and microscopic stool particles, leading to a condition called pruritus ani (anal itching). The problem worsens if you repeatedly wipe to relieve the itch.
Anatomy of hemorrhoids
Hemorrhoids are distended blood vessels that form either externally (around the anus) or internally (in the lower rectum).
What causes hemorrhoids?
Experts don't fully agree, but several mechanisms are probably at work. Large, prolapsing hemorrhoids are associated with chronic constipation, straining during bowel movements, and prolonged sitting on the toilet — all of which can cause blood to pool and enlarge the vessels. Inadequate fiber intake may also contribute.
People with hemorrhoids tend to have a higher than average resting anal canal tone — that is, the smooth muscle of the anal canal is tighter than average, even when they're not straining. Constipation adds to the trouble, because straining during a bowel movement increases pressure in the anal canal and pushes the hemorrhoids against the sphincter muscle. Finally, hemorrhoids may bulge and prolapse because the connective tissues that support and hold them in place become weaker with age.
Hemorrhoids can usually be diagnosed from a simple medical history and physical exam. External hemorrhoids are generally visible, especially if a blood clot has formed. Your clinician may perform a digital rectal exam to check for blood in the stool. She or he may also examine the anal canal with an anoscope, a short, lighted plastic tube inserted into the rectum. If there's evidence of rectal bleeding or blood in the stool, a sigmoidoscopy or colonoscopy may be recommended to rule out conditions such as colorectal polyps or cancer, especially in people over age 50.
For purposes of determining the best treatment, internal hemorrhoids are often classified according to the degree of protrusion into the anal canal. First-degree hemorrhoids don't protrude, and they may or may not bleed; second-degree hemorrhoids protrude with defecation and retract on their own; third-degree hemorrhoids protrude and must be manually reduced (pushed back into their normal position); and fourth-degree hemorrhoids protrude and cannot be reduced.