An ostomy is the broad term for any surgery that creates an opening in the body to reroute waste. A colostomy is one specific type of ostomy, where that opening is made in the large intestine (colon). Think of it this way: every colostomy is an ostomy, but not every ostomy is a colostomy. The confusion is understandable because “colostomy” is the most common version, making up roughly 50 to 60 percent of all ostomies in the United States.
Ostomy Is the Umbrella Term
An ostomy refers to a surgically created opening, called a stoma, on the surface of your abdomen. Waste exits the body through this opening and collects in a pouch rather than following its usual route. The word tells you nothing about where the opening connects internally. That’s where the specific names come in.
The three most common types are:
- Colostomy: connects to the large intestine (colon)
- Ileostomy: connects to the small intestine (ileum)
- Urostomy: reroutes urine from the kidneys out through a stoma, bypassing the bladder entirely
Between 800,000 and 1,000,000 people in the United States live with some form of ostomy. When someone says “I have an ostomy” without specifying, they could have any of these three.
Where a Colostomy Connects to the Colon
A colostomy can be placed at different points along the large intestine, and the location matters because it directly affects what comes out. The colon’s main job is absorbing water from digested food. The further along the colon the stoma is placed, the more water has been absorbed and the firmer the output.
There are four types, named for their position:
- Ascending colostomy: placed in the first section of the colon, running up the right side of the abdomen. Output is loose, pasty, or watery because very little water has been reabsorbed yet.
- Transverse colostomy: placed in the section that stretches horizontally across the upper abdomen.
- Descending colostomy: placed in the section running down the left side. Output is usually soft.
- Sigmoid colostomy: placed in the last section before the rectum. Output can be soft or firm, closest to a normal bowel movement.
Sigmoid and descending colostomies are the most common. Because their output is more predictable, some people with these types can develop a regular schedule and even use closed-end pouches that get discarded after a single use.
How an Ileostomy Differs
An ileostomy connects to the small intestine, which sits upstream of the colon entirely. Because food hasn’t yet passed through the colon for water absorption, ileostomy output is consistently liquid. There is no control over when stool or gas exits the stoma, so a collection pouch must be worn at all times. The pouch attaches to the skin around the stoma with an adhesive barrier and collects everything continuously.
This makes daily management different from a colostomy. People with an ileostomy typically empty their pouch multiple times a day and need to pay closer attention to hydration, since less water is being reclaimed by the body. A colostomy placed lower on the colon, by contrast, may only need attention once or twice a day.
What a Stoma Looks and Feels Like
Regardless of the type of ostomy, the stoma itself looks similar. It’s a small, moist, pinkish-red circle of tissue that protrudes slightly from the abdomen. Right after surgery it tends to be swollen, but it shrinks over the following weeks. A healthy stoma has no nerve endings on its surface, so touching it doesn’t cause pain. You won’t feel waste passing through it either.
The stoma does not have a muscle to open and close, which is why an external pouching system is necessary. The one exception is certain sigmoid colostomies, where some people learn a technique called irrigation (essentially a colonic flush on a schedule) that can allow them to go hours without a pouch.
Temporary Versus Permanent
Both colostomies and ileostomies can be temporary or permanent. A temporary ostomy is created to give a section of the bowel time to heal after surgery, injury, or infection. Once healing is complete (often weeks to months later), a second surgery reconnects the intestine and closes the stoma.
A permanent ostomy is necessary when the affected section of the bowel has been removed entirely or can no longer function. Colorectal cancer, severe inflammatory bowel disease, and traumatic injuries are among the most common reasons. Whether the ostomy stays or goes depends on how much healthy bowel remains and whether the rectum and anal sphincter are still intact.
Pouching Systems and Daily Management
All ostomy types use the same basic equipment: a skin barrier (also called a wafer) that adheres to the skin around the stoma, and a pouch that collects output. From there, the options branch out depending on lifestyle and stoma characteristics.
One-piece systems combine the barrier and pouch into a single unit. Changing the pouch means peeling off the barrier too. Two-piece systems keep the barrier in place on the skin while letting you snap a fresh pouch on and off. The two-piece design is popular because it reduces how often you’re pulling adhesive off your skin, which cuts down on irritation.
Pouches themselves come in two styles. Drainable pouches open at the bottom so you can empty them while they’re still attached, then reseal with a clip or built-in closure. Closed-end pouches are sealed at the bottom and thrown away after one use. People with predictable, firmer output (typically from a sigmoid or descending colostomy) often prefer closed-end pouches. Those with liquid output from an ileostomy or ascending colostomy almost always use drainable ones.
Accessories round out the toolkit. Barrier paste or rings fill in uneven skin around the stoma to prevent leaks. Ostomy belts wrap around the waist and clip to the pouch for extra security. Adhesive removers help with painless wafer changes, and skin barrier wipes protect the surrounding skin from irritation. The specific combination varies from person to person, and most people fine-tune their setup over the first few months.
Quick Comparison at a Glance
- Ostomy: any surgically created opening for waste to exit the body. Includes colostomies, ileostomies, and urostomies.
- Colostomy: a specific ostomy connecting the colon to the abdominal surface. Output ranges from watery to firm depending on placement.
- Ileostomy: connects the small intestine to the surface. Output is always liquid.
- Urostomy: reroutes urine. Not related to the intestines at all.
When you see “ostomy” used alone, it’s the general category. When you see “colostomy,” “ileostomy,” or “urostomy,” you’re getting the specific type, which tells you exactly which organ is involved and what kind of output to expect.