Overview

Hemorrhoids Open pop-up dialog box Close Hemorrhoids Hemorrhoids Hemorrhoids are swollen veins in your lower rectum. Internal hemorrhoids are usually painless, but tend to bleed. External hemorrhoids may cause pain.

Hemorrhoids (HEM-uh-roids), also called piles, are swollen veins in your anus and lower rectum, similar to varicose veins. Hemorrhoids can develop inside the rectum (internal hemorrhoids) or under the skin around the anus (external hemorrhoids).

Nearly three out of four adults will have hemorrhoids from time to time. Hemorrhoids have a number of causes, but often the cause is unknown.

Fortunately, effective options are available to treat hemorrhoids. Many people get relief with home treatments and lifestyle changes.

Products & Services Book: Mayo Clinic on Digestive Health

Symptoms

Signs and symptoms of hemorrhoids usually depend on the type of hemorrhoid.

External hemorrhoids

These are under the skin around your anus. Signs and symptoms might include:

Itching or irritation in your anal region

Pain or discomfort

Swelling around your anus

Bleeding

Internal hemorrhoids

Internal hemorrhoids lie inside the rectum. You usually can't see or feel them, and they rarely cause discomfort. But straining or irritation when passing stool can cause:

Painless bleeding during bowel movements. You might notice small amounts of bright red blood on your toilet tissue or in the toilet.

A hemorrhoid to push through the anal opening (prolapsed or protruding hemorrhoid), resulting in pain and irritation.

Thrombosed hemorrhoids

If blood pools in an external hemorrhoid and forms a clot (thrombus), it can result in:

Severe pain

Swelling

Inflammation

A hard lump near your anus

When to see a doctor

If you have bleeding during bowel movements or you have hemorrhoids that don't improve after a week of home care, talk to your doctor.

Don't assume rectal bleeding is due to hemorrhoids, especially if you have changes in bowel habits or if your stools change in color or consistency. Rectal bleeding can occur with other diseases, including colorectal cancer and anal cancer.

Seek emergency care if you have large amounts of rectal bleeding, lightheadedness, dizziness or faintness.

Causes

The veins around your anus tend to stretch under pressure and may bulge or swell. Hemorrhoids can develop from increased pressure in the lower rectum due to:

Straining during bowel movements

Sitting for long periods of time on the toilet

Having chronic diarrhea or constipation

Being obese

Being pregnant

Having anal intercourse

Eating a low-fiber diet

Regular heavy lifting

Risk factors

As you age, your risk of hemorrhoids increases. That's because the tissues that support the veins in your rectum and anus can weaken and stretch. This can also happen when you're pregnant, because the baby's weight puts pressure on the anal region.

Complications

Complications of hemorrhoids are rare but include:

Anemia. Rarely, chronic blood loss from hemorrhoids may cause anemia, in which you don't have enough healthy red blood cells to carry oxygen to your cells.

Rarely, chronic blood loss from hemorrhoids may cause anemia, in which you don't have enough healthy red blood cells to carry oxygen to your cells. Strangulated hemorrhoid. If the blood supply to an internal hemorrhoid is cut off, the hemorrhoid may be "strangulated," which can cause extreme pain.

If the blood supply to an internal hemorrhoid is cut off, the hemorrhoid may be "strangulated," which can cause extreme pain. Blood clot. Occasionally, a clot can form in a hemorrhoid (thrombosed hemorrhoid). Although not dangerous, it can be extremely painful and sometimes needs to be lanced and drained.

Prevention

The best way to prevent hemorrhoids is to keep your stools soft, so they pass easily. To prevent hemorrhoids and reduce symptoms of hemorrhoids, follow these tips: