Mass formed by distension of the network of veins supplying the anal canal. It may develop from infection or increased abdominal pressure (as in pregnancy or heavy lifting). Mild hemorrhoids may require only ointments, laxatives, and baths. If clotting, bleeding, or pain occurs, surgical removal may be needed. Internal hemorrhoids, with little nerve supply, can be destroyed in several ways without anesthesia. External hemorrhoids, under the skin, are cut out under local anesthesia.

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