Last reviewed on 01/18/2021. Learn more about our editorial process. Hemorrhoids (piles) are swollen veins that form inside of your rectum or outside of your anus. They often go away without medical treatment.

Hemorrhoids are nothing less than vascular dilatations of the venous plexuses that supply the anal region. They may cause bleeding, itching and even exit from the dilated structure through the anal orifice. The larger the hemorrhoid, means that there is a greater extent of dilation, which directly implies treatment. Currently, the classification of the disease varies between grades I and IV, and grades III and IV dilations (prolapse of the structure through the anal canal on exertion, requiring manual maneuver to return to the site or not returning even with assistance) are commonly indicative of surgical treatment.

Hemorrhoids are when the veins or blood vessels in and around your anus and lower rectum become swollen and irritated. This happens when there is extra pressure on these veins. Hemorrhoids can be either inside your anus (internal) or under the skin around your anus (external). They are very common in both men and women.

The first use of the word "hemorrhoid" in English occurs in 1398, derived from the Old French "emorroides", from Latin hæmorrhoida, in turn from the Greek αἱμορροΐς ( haimorrhois ), "liable to discharge blood", from αἷμα ( haima ), "blood" and ῥόος ( rhoos ), "stream, flow, current", itself from ῥέω ( rheo ), "to flow, to stream".