Approved by the Cancer.Net Editorial Board, 06/2019

A colostomy is a surgery that makes a temporary or permanent opening called a stoma. A stoma is a path that goes from the large intestine to the outside of your abdomen. This helps solid waste and gas exit the body without passing through the rectum. The waste is collected in a pouch worn on the outside of your body.

What is the large intestine?

The large intestine is made up of the colon and rectum. It is connected to the small intestine. The small intestine digests nutrients and absorbs them into blood vessels. These nutrients include proteins, fats, and carbohydrates. Remaining food that cannot be digested moves from the small intestine to the colon. The colon absorbs water from the waste and stores the waste until the next bowel movement.

This illustration shows the 5 sections of the colon and rectum. The ascending colon is the beginning the large intestine into which the small intestine empties; it begins on the lower right side of the abdomen and then leads up to the transverse colon. The transverse colon crosses the top of the abdomen from right to left, leading to the descending colon, which takes waste down the left side. Finally, the sigmoid colon at the bottom takes waste a few more inches, down to the rectum. A cross-section of the rectum and sigmoid colon shows where waste leaves the body, through the anus. Copyright 2004 American Society of Clinical Oncology. Robert Morreale/Visual Explanations, LLC.

Why do I need a colostomy?

A doctor may do a colostomy to bypass or remove part of the lower intestine. This may be because:

  • The large intestine is blocked or damaged

  • A part of the large intestine is surgically removed

  • A ruptured colon causes an abdominal infection

People with certain types of cancer, such as colorectal cancer, may need a colostomy. Sometimes people being treated for prostate, ovarian, uterine, or cervical cancer need a colostomy. People with Crohn’s disease, ulcerative colitis, or pre-cancerous colon polyps may also need an colostomy.

How long will I need a colostomy?

Most people who need a cancer-related colostomy only need it for a few months while the colon or rectum heals. But some people may need a permanent colostomy.

Types of colostomy

Each type is named for the section of the colon in which it is needed.

  • Sigmoid colostomy. This is the most common type. It is located in the bottom part of the large intestine. The sigmoid colon moves waste to the rectum. Sigmoid colostomies produce stool that is more solid and regular than other colostomies.

  • Transverse colostomy. The transverse colon crosses the top of the abdomen. Stool in this area is usually soft. This is because only a small portion of the colon has absorbed water from the indigestible material. This common type of colostomy has 3 versions:

    • A loop colostomy. This colostomy creates a stoma through which stool exits. In this type, the colon stays connected to the rectum. As a result, people will sometimes pass stool or gas through the rectum.

    • A single-barrel colostomy. This surgery removes the colon below the colostomy, including the rectum and anal opening. This type of colostomy is permanent.

    • A double-barrel colostomy. This divides the colon into 2 ends that form separate stomas. Stool exits from 1 of the stomas. Mucus made by the colon exits from the other. This type of transverse colostomy is the least common.

  • Descending colostomy. The descending colon takes waste down the left side of the abdomen. The stool there is usually firm because it has moved through the working parts of the colon.

  • Ascending colostomy. The ascending colon runs from the beginning of the large intestine to the right side of the abdomen. In this procedure, only part of the colon still works. As a result, little water is absorbed from the waste. This means the stool is usually liquid. This type of colostomy is rare. An ileostomy is more appropriate for this portion of the colon.

What should I expect during surgery?

You will receive general anesthesia before the surgery. During the surgery, the surgeon attaches 1 end of the colon to a stoma in a place where you can see and care for it. Then the surgeon attaches the colostomy bag to the stoma.

The procedure may be done with:

  • A surgical incision, which is a large cut in the abdomen

  • Laparoscopic surgery, which involves less invasive small cuts. This method reduces pain and recovery time.

Surgery may include the following risks:

  • Bleeding inside the colon

  • Damage to nearby organs

  • Infection

  • Bleeding from the stoma

How long will it take to recover from surgery?

Most people stay in the hospital for up to 1 week after the procedure. Complete recovery from a colostomy may take up to 2 months. During this time, you will have limits on what you can eat while the colon heals.

If the colostomy is temporary, you may need a reversal, or closure, surgery after the colon has healed. This surgery usually takes place about 3 months later.

Colostomy care

Emptying your colostomy bag. Once you have recovered from surgery, you will need to empty the colostomy bag several times per day. You will not be able to control when stool and gas move into the pouch. It is best to empty it when the bag is less than half full.

Colostomy pouches come in many sizes and shapes, but there are 2 main types:

  • One-piece pouches attach directly to the skin barrier.

  • Two-piece pouches include a skin barrier and a pouch that can detach from the body.

Other options include open-end or drainable and closed-end or disposable pouches. Ask your health care team about which type of colostomy pouch you will receive.

Caring for your skin. The skin surrounding the stoma is called peristomal skin. It will always look red and may bleed occasionally, which is normal. But bleeding should not continue for long.

It is important to make sure your pouch is correctly connected to your stoma. Pouches that do not fit well can irritate the skin. You should also keep this area clean and dry. If this skin appears wet, bumpy, itchy, or painful, contact your health care team. It is possible that the area may be infected.

Colostomy concerns

High stool output. During the first few days after surgery, you may have a larger than normal stool output. As your body gets used to the stoma and colostomy, this amount will decrease. But if it does not decrease after a few days, call your health care team. Passing large amounts of stool means you may be losing too many fluids. This could lead to an imbalance in your electrolyte levels. Electrolytes are minerals that help regulate the body.

Managing gas. Just like with stool, you will also need to release gas from your colostomy pouch. The way you do this depends on the type of pouch. Some pouches have a filter that deodorizes and vents gas. This prevents the bag from becoming too stretched, coming off of the abdomen, or bursting.

Amounts of gas deposited into the pouch will vary based on the type of colostomy and your diet. Foods and drinks such as beans, onions, milk, and alcohol can cause excess gas. Swallowing air can also increase the amount of gas in your colon. This happens when you chew gum or drink through a straw. You may have a lot of gas right after surgery. But this should decrease as your body heals. Your health care team can provide information on food and lifestyle choices to help reduce gas.

Whole pills or capsules in stool. Coated pills and extended-release capsules may come out intact in your pouch. This can mean that the medication was not fully absorbed in your body. Tell your health care team if this happens. They may be able to prescribe liquid or gel medications for you to take instead.

Stoma obstruction. Sometimes your stoma may become blocked by a piece of undigested food and scar tissue. This means that stool and gas cannot pass into the pouch. An obstruction may cause abdominal pain or swelling or nausea and vomiting.

You may be able to remove the blockage at home. This can be done by avoiding solid foods and drinking more fluids, including warm drinks like tea. You can also try massaging your abdomen around the stoma or drawing your knees to your chest and rocking side to side. If these tips do not work, call your health care team right away.

Related Resources

Living With an Ostomy Bag

Life with an Ostomy Bag: 3 Tips for Thriving

Blocked Intestine or Gastrointestinal Obstruction

More Information

MedlinePlus: Colostomy