What Is It?
Hemorrhoids are lumps or masses of tissue in the anus, which contain enlarged blood vessels. Any increase in abdominal pressure may produce hemorrhoids. This may be from:
- Repeated straining to have a bowel movement, especially in people who suffer from frequent constipation.
- Repeated episodes of diarrhea.
- Many patients have no apparent explanation for the formation of hemorrhoids, however.
Internal hemorrhoids. Internal hemorrhoids lie inside the anal canal, where they primarily cause the symptom of intermittent bleeding, usually with bowel movements, and sometimes mucous discharge. They are usually painless. Internal hemorrhoids also may protrude (prolapse) outside the anus, where they appear as small, grape-like masses. Usually the prolapsed hemorrhoid can be pushed back into the anus with a fingertip.
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