Thrombosed External Hemroids 

Definition
Hemroids are enlarged veins in the anus or lower rectum. They often go unnoticed and usually clear up after a few days, but can cause long-lasting discomfort, bleeding and be excruciatingly painful. Effective medical treatments are available, however.

Description
Hemroids (also called piles) can be divided into two kinds, internal and external. Internal hemroids lie inside the anus or lower rectum, beneath the anal or rectal lining. External hemroids lie outside the anal opening. Both kinds can be present at the same time.

Hemroids are a very common medical complaint. More than 75% of Americans have hemroids at some point in their lives, typically after age 30. Pregnant women often develop hemroids, but the condition usually clears up after childbirth. Men are more likely than women to suffer from hemroids that require professional medical treatment.

Causes and symptoms
Precisely why hemroids develop is unknown. Researchers have identified a number of reasons to explain hemroidsal swelling, including the simple fact that people's upright posture places a lot of pressure on the anal and rectal veins. Aging, obesity, pregnancy, chronic constipation or diarrhea, excessive use of enemas or laxatives, straining during bowel movements, and spending too much time on the toilet are considered contributing factors. Heredity may also play a part in some cases. There is no reason to believe that hemroids are caused by jobs requiring, for instance, heavy lifting or long hours of sitting, although activities of that kind may make existing hemroids worse.