Laxatives in the form of fiber may help ease symptoms of hemorrhoids, especially bleeding, researchers report.

Hemorrhoids are swollen blood vessels in the rectum. Some lie far enough inside the rectum that they don’t hurt and aren’t visible. Others lie within the anus and are usually painful.

Hemorrhoids are common. About half of people in the U.S. will have them at some point. Most people are affected sometime between ages 20 and 50.

Hemorrhoids usually aren’t a serious medical problem, but they can be painful. They often are a cause of rectal bleeding. More serious conditions (such as colon cancer and diverticulosis) can also cause bleeding. See a doctor to rule out those problems.

Cause, Treatments

The cause of bothersome hemorrhoids isn’t known, but constipation can contribute.

“The initial approach is to increase the amount of water and fiber in the diet, or to introduce a laxative,” write Pablo Alonso-Coello and colleagues in The Cochrane Library.

Alonso-Coello works at the Iboamerican Cochrane Centre at the Hospital de la Santa Creu I Sant Pau in Barcelona, Spain.

Surgery can also be done to treat more severe hemorrhoids.

Seven Studies Reviewed

The researchers reviewed seven studies. Each study compared fiber laxatives with no treatment (placebos). The laxatives contained fiber in various forms.

The studies had between 28 and 92 participants in each. Rectal bleeding was their main complaint.

The reviewers found a “beneficial effect of laxatives in the form of fiber for improving symptoms of hemorrhoids, especially bleeding.”

How big was the improvement? The patients who took fiber laxatives were about half as likely to have persistent symptoms as those who got the placebos.

Bleeding particularly improved. There was no clear pattern for other symptoms, such as itching, pain, and prolapse (in which hemorrhoids slip down and out of the anal canal).

The studies were fairly small, and their quality could have been better, the researchers note.

Most patients had relatively mild symptoms, the reviewers note.

“While fiber might also be effective in people with more advanced states of hemorrhoidal disease, this remains largely unaddressed,” they write.

By Miranda Hitti, reviewed by Louise Chang, MD

SOURCES: Alonso-Coello, P. The Cochrane Library, 2005; issue 4. WebMD Medical Reference: “Understanding Hemorrhoids -- the Basics.” WebMD Reference provided in collaboration with The Cleveland Clinic: “Digestive Diseases: Surgery to Treat Hemorrhoids.” News release, John Wiley & Sons, Inc.