Most colorectal polyps are benign. However, large polyps can cause constipation and other symptoms and are more likely to be cancerous.

Colorectal polyps are small growths that form on the lining of the colon or rectum. They typically measure less than 1 centimeter (cm), though they can grow as large as several centimeters.

Colorectal polyps are common, affecting between 20–30% of adults in the U.S. Most are benign, though some may be precancerous, meaning they become cancerous over time.

Constipation is a condition in which a person experiences one or more of the following:

  • fewer than 3 bowel movements per week
  • stools that are hard, dry, or lumpy
  • pain or difficulty passing stools
  • a sensation of incomplete bowel emptying

In this article, we go over the association between polyps and constipation, whether colorectal polyps can cause other symptoms or colorectal problems, and the treatment for constipation caused by colorectal polyps.

Most colorectal polyps do not cause any symptoms. However, large colorectal polyps may cause changes in the frequency of bowel habits. Some people may develop constipation, while others may experience diarrhea.

A 2019 case study reports on a 28-year-old woman who developed intestinal obstruction due to a large colorectal polyp measuring 4 cm, which tests later found to be cancerous. In this case, the polyp caused a type of obstruction called intussusception, in which one part of the bowel slides into another, causing it to collapse like a telescope.

The woman went to the emergency department with abdominal pain and watery diarrhea. Typically, a bowel obstruction also causes constipation, as it can prevent stools from passing through the colon. Watery diarrhea can occur when only liquid stool can get past the obstruction.

Larger polyps are more likely to cause a bowel obstruction and associated complications, such as diarrhea or constipation. The American Cancer Society (ACS) adds that larger polyps are also more likely to be cancerous.

Besides diarrhea and constipation, some other potential symptoms of bowel obstruction include:

  • feeling bloated and full
  • abdominal pain
  • nausea
  • vomiting large amounts of undigested food or bowel fluid
  • inability to pass gas
  • atypical bowel sounds

Additionally, certain types of polyps are precancerous, meaning they can turn cancerous over time. The ACS lists three types of polyps that have the potential to become cancerous. These are:

  • Adenomatous polyps (APs): Doctors may refer to these polyps as “precancerous” because they can change into cancer. They are further subdivided into three types:
    • tubular adenomas, which are the most common APs but also the least likely to become cancerous
    • villous adenomas, which are the least common APs but the most likely to become cancerous
    • tubulovillous adenomas
  • Sessile serrated polyps (SSPs) and traditional serrated adenomas (TSAs): Doctors often treat these like APs because they have a higher likelihood of becoming cancerous.
  • Hyperplastic and inflammatory polyps: These are more common but are typically not precancerous. Nonetheless, people with hyperplastic polyps larger than 1 cm may require more frequent colonoscopies to screen for colorectal cancer.

Colorectal polyps do not usually cause symptoms, and most people only become aware of their existence following tests or screenings for other bowel conditions. Rarely, large polyps may cause symptoms such as:

  • small amounts of blood or mucus in stools
  • rectal bleeding
  • a change in your normal bowel habits, such as diarrhea or constipation
  • unexplained weight loss

Do polyps cause gas and bloating?

Large polyps may cause a bowel obstruction and associated symptoms, such as a sensation of fullness or bloating. However, a bowel obstruction also typically results in an inability to pass gas.

You should see a doctor if you suspect you may have a colorectal polyp, especially if you have a personal or family history of colorectal polyps.

It’s also important to see a doctor if you experience any of the following symptoms:

  • mucus or blood in your stools, lasting 3 weeks or more
  • changes to your usual bowel habits
  • chronic constipation that does not improve with treatment, or occurs regularly and lasts a long time
  • unexplained weight loss
Medical emergency

Some gastrointestinal symptoms indicate a need for urgent medical attention. Go to the nearest emergency room if you experience any of the following:

  • diarrhea lasting more than 7 days
  • stools that are dark red or black
  • bloody diarrhea

A large polyp that is causing constipation or other bothersome symptoms may require cauterization or snaring.

Both procedures involve passing a flexible instrument called a colonoscope into the anus and up into the bowel. The end of the colonoscope has a wire with an electric current, which the surgeon uses to burn off (cauterize) or slice off (snare) the polyp.

Polyps can recur, so you may need follow-up colonoscopies every 3–5 years to check for any new growths.

Some general treatments for constipation include:

  • eating more fiber-rich foods while also drinking more water and other fluids
  • exercising regularly to stimulate the bowel
  • going to the bathroom at the same time each day
  • giving yourself enough time to have a bowel movement
  • going to the bathroom as soon as you feel the urge
  • putting your feet on a footstool to help relax the pelvic floor muscles during a bowel movement
  • taking medication to help ease constipation, such as:

Below are some answers to frequently asked questions (FAQ) about polyps.

Can polyps protrude from your anus?

If they are large enough, it’s possible for polyps to protrude from the anus. If that is the case, they are likely to be cancerous.

A 2022 study investigated post-surgical outcomes following rectal polyp removal and noted that most of the polyps had grown within 6–11 cm of the anus.

A 2018 case study features a rare case of a person passing an adenomatous polyp during a bowel movement. In this case, a 60-year-old man had experienced several weeks of persistent constipation and worsening abdominal pain prior to passing the polyp. The study authors noted that this is the first published case of spontaneous expulsion of an AP during defecation.

How long do polyps take to grow in the bowel?

Because polyps rarely cause symptoms, it’s difficult to say how long they take to grow.

However, the ACS notes that a polyp can take between 10 and 15 years to develop into cancer. It adds that bowel screening can help doctors detect and remove polyps before they have a chance to turn cancerous.

What foods should you avoid if you have polyps?

It’s not clear whether people with polyps should avoid certain foods. However, limiting the following foods may help to prevent polyps:

  • fatty or fried foods
  • red meats like beef and pork
  • processed meats, such as bacon, sausage, hot dogs, and lunch meats

Dietary changes that help to prevent polyps may help reduce the risk of recurrent polyps in people who have had a polyp removed.

Colorectal polyps are small growths that develop on the lining of the colon or rectum.

Most polyps do not cause any symptoms, but large polyps can cause changes in bowel habits, such as constipation or diarrhea. They may also cause intestinal obstruction and associated symptoms, such as abdominal pain, bloating, and an inability to pass gas.

You should contact a doctor if you suspect you may have a colorectal polyp, especially if you have a family history of such polyps.

If a large polyp is causing constipation or other issues, a doctor may recommend removing it surgically. While most polyps are benign, some can develop into cancer, so doctors will typically check polyps for signs of precancer or cancer.

It’s common for polyps to regrow after removal.