Ostomy bags are pouches worn on the outside of the body to collect waste, either stool or urine, that has been surgically rerouted away from its normal path. When disease, injury, or a birth defect makes it unsafe or impossible for waste to exit through the anus or bladder, surgeons create a small opening in the abdomen called a stoma. The stoma connects directly to the intestine or urinary tract, and an ostomy bag attaches over it to catch everything that comes out. Between 725,000 and 1 million people in the United States live with an ostomy.
Why Someone Might Need an Ostomy
An ostomy becomes necessary when part of the digestive or urinary system is damaged, blocked, or needs to be removed entirely. The most common reasons include inflammatory bowel disease (Crohn’s disease and ulcerative colitis), colorectal or anal cancer, bladder cancer, traumatic injury to the abdomen, bowel obstruction, and certain conditions present at birth. In each case, waste can no longer safely travel its usual route, so surgeons redirect it to exit through the abdominal wall instead.
Some ostomies are permanent, meaning the affected section of bowel or bladder has been removed and cannot be reconnected. Others are temporary, created to give a diseased or injured section of the intestine time to heal. A temporary ostomy is typically reversed after three to twelve months, once the surgeon confirms the bowel has recovered enough to function on its own again.
Three Main Types of Ostomy
The type of ostomy depends on which part of the body is being bypassed. Each produces different output, which affects what kind of bag is used and how often it needs attention.
- Colostomy: A portion of the large intestine (colon) is brought through the abdominal wall, usually on the left side. Stool consistency varies by location. A colostomy made from the upper colon produces loose or watery output, while one made from the lower colon produces soft to firm stool that more closely resembles a normal bowel movement.
- Ileostomy: The end of the small intestine (ileum) is brought through the abdominal wall, typically on the right side. Because food hasn’t yet passed through the large intestine where water is absorbed, the output is consistently liquid to pasty. There is no voluntary control over when stool or gas exits.
- Urostomy: A small segment of intestine is used to create a channel that redirects urine from the kidneys to the stoma, bypassing the bladder entirely. The bag collects urine continuously, since there is no sphincter to hold it back.
How an Ostomy Bag Works
The bag itself is just one part of what’s called a pouching system. Every system includes a skin barrier (also called a wafer), which is an adhesive piece that sticks to the skin around the stoma and creates a seal, and the pouch that collects waste. The opening in the barrier is sized to fit snugly around the base of the stoma so nothing leaks underneath.
Pouching systems come in two main designs. A one-piece system combines the barrier and pouch into a single unit, making it thinner and lower-profile under clothing. A two-piece system separates the barrier from the pouch, connecting them with a snap-style ring. This lets you swap out the pouch without peeling the adhesive off your skin each time, and gives you the flexibility to switch between different pouch sizes or styles while keeping the same barrier in place.
Most modern pouches include a charcoal filter that neutralizes the smell of intestinal gas as it’s released, so gas doesn’t build up and balloon the pouch. The filter handles most odor effectively, though certain foods, particularly sulfur-rich vegetables, can produce gas strong enough to get past it.
Emptying and Changing the Pouch
You empty a pouch when it’s about one-third full. Letting it fill beyond that puts strain on the adhesive seal and increases the risk of leaks. How often that happens depends on the type of ostomy and your diet, but for most people it means several times a day.
The full pouching system, including the skin barrier, needs to be changed every two to four days. With a two-piece system, you may change just the pouch more frequently while leaving the barrier in place longer. If you notice itching, burning, or the edges of the barrier starting to lift, it’s time to change regardless of the schedule.
Protecting the Skin Around the Stoma
The skin surrounding the stoma takes a lot of wear. It’s exposed to adhesive, moisture, and potentially digestive enzymes or urine if the seal isn’t tight. The most common problems are irritation from prolonged moisture exposure (redness, softened skin, or fungal rashes) and damage from repeatedly removing the adhesive (skin stripping, blistering, or inflamed hair follicles).
Keeping the barrier opening properly sized is the single most important step. If the opening is too large, skin is exposed to waste. If it’s too small, it can press against the stoma. When changing the barrier, push down gently on the skin rather than pulling the adhesive away, and use a medical adhesive remover if needed. Clean the area with plain water and a soft cloth. Avoid harsh soaps or products that increase stickiness, like tincture of benzoin, which can make skin stripping worse.
If the skin around the stoma is uneven, has creases, or the stoma sits flush or slightly retracted, accessories can help. Barrier rings are flexible, moldable strips that fill in dips and folds to create a flatter surface for the adhesive. Skin barrier paste works like caulk, sealing small gaps between the stoma and the wafer to prevent output from sneaking underneath. Barrier extenders are adhesive strips that hold down the edges of the wafer, reducing lift and extending wear time. An ostomy belt wraps around the body and clips to the pouch flanges for extra security during physical activity. It should be snug enough to stay in place but loose enough to slide two fingers between the belt and your skin.
Daily Life With an Ostomy Bag
Modern ostomy pouches are designed to be discreet. One-piece systems sit flat against the body and are difficult to detect under most clothing. The charcoal filters handle gas silently and without noticeable odor in most situations. People with ostomies swim, exercise, travel, and work without restrictions, though high-contact sports may require a protective cover over the stoma.
Diet adjustments are common, especially in the first few weeks. Foods that produce excess gas or very loose stool can make pouch management harder. Most people gradually learn which foods work well and which ones to moderate. Staying hydrated matters more with an ileostomy, since the large intestine, which normally absorbs water, has been bypassed.
The pouch can be emptied in any standard restroom. Drainable pouches have a clip or integrated closure at the bottom that opens over the toilet. Closed-end pouches, more common with colostomies that produce firmer output, are simply removed and discarded. The whole process takes a few minutes and, with practice, becomes routine.