What is a stoma?


Digestive system

When you swallow food and drink it travels from your mouth, down your oesophagus (or gullet) towards your stomach. Your stomach contains digestive juices which break the food down into a paste that then moves into your small intestine. Your small intestine is a long structure that plays a very important role in your digestive system. It is here that the nutrients from our food that we require for survival are absorbed. The small intestine consists of the duodenum, the jejunum and the ileum. Once the food has moved through the small intestine most of the nutrients and liquid have been absorbed and what is left now gets passed into the large intestine (also known as the colon). You may like to think of the large intestine as a tumble dryer. As your food waste moves through your large intestine, the moisture is absorbed and the waste becomes drier and more formed so that by the time it reaches your rectum it is a well formed stool. It is at this point that you get the sensation of needing to empty your bowels and, when you are ready, your stool will exit your rectum via the natural opening in your bottom, which is your anus.


Your Urinary System

The water that your digestive system has extracted from your food and drink passes into your blood stream for your body to use. This blood passes through your kidneys for cleaning and the kidneys remove any waste. Waste products, along with water, become urine, which travels from the kidneys down to the urinary bladder via the ureters. It is stored in the bladder until you are ready to urinate and then it travels from the bladder, along the urethra to the outside world.


A stoma (or ostomy, these 2 words mean the same thing) is a surgically created opening on the abdomen which allows stool or urine to exit the body. There are 3 main types of stoma – colostomy, ileostomy and urostomy. You should ask your medical team which type of stoma you have/are going to have as there are some differences between them.


Generally, your stoma will be pink and moist (like the inside of your mouth) and a little swollen after your operation. This will reduce over a period of between six to eight weeks. There are no nerves in your stoma so there will not be any sensation when you touch it. Everyone’s stoma is different in shape and size, so don’t worry if yours doesn’t look like the ones in this leaflet.



Colostomy is the term used to describe an opening from the large intestine (colon). The surgeon will bring a part of the colon from inside your body, through the abdomen to the outside and stitch it down to secure it. Normally this will be on the left side of your abdomen.

  • Formation of a colostomy

Usually, you will need to wear a bag over the colostomy to collect your stool as there is no way to control when the stool will be released. Wind will also be collected in the bag but the bag will have a filter that allows this wind to be passed without allowing odour to escape. The bag will be closed across the bottom and will need to be changed after each bowel motion. The amount of times you need to change the bag can vary but is normally between 1 and 3 times a day. It is possible that you will change your bag more than this in the early post-operative period, but it will reduce as your system recovers and settles down.



Ileostomy is the term used to describe an opening from the small intestine, specifically the ileum. The surgeon will bring a part of the small bowel from inside your body to the surface where it will be stitched down to secure it. Normally this will be on the right hand side of your abdomen.

  • Ileostomy formation

An ileostomy works almost continuously and you won’t have any control over this, although some people find there are times of the day when their stoma is less active. You will wear a drainable bag over your ileostomy to collect your output. The drain at the bottom of the bag is secured with either a clip or Velcro. The bag will have a filter that allows flatus to be passed without allowing odour to escape. The number of times people empty their ileostomy bags varies greatly and may be anywhere between 4-12 times per day. As with a colostomy, it is likely that your stoma will produce more output in the first few weeks and months after surgery, but this will decrease as things settle down.


Types of colostomy and ileostomy

There are two main types of colostomy and ileostomy – loop and end. Either type of stoma may be temporary or permanent. Your medical team will be able to tell you which kind you have. To create a loop stoma, a loop of intestine is brought through the abdominal wall (and supported by a temporary rod, Fig 1). This loop is partially opened to form a stoma with two openings (Fig 2), although you may only be able to see one.


One opening is still connected to the functioning part of your digestive system and is where your output will come through. The other opening leads down to the lower part of your digestive system and may discharge a small amount of mucus, but will otherwise be inactive.


An end stoma is made by bringing one end of the intestine out through the abdominal wall. There is only one opening from an end stoma and this is where your output will come through.



Urostomy (also known as an ileal conduit) is the term used to describe an opening for your urine. A urostomy is made by taking a piece of your small intestine and attaching it to your ureters to create a channel for urine to pass through. One end of the tube is brought out through the abdomen to create a urostomy. Depending on your operation sometimes the bladder is removed, but this will be discussed with you prior to your operation. Urostomies are normally on the right hand side of your abdomen and will have a little spout to allow the urine to exit the body.


After the operation there will be stents in the urostomy and these usually come out after 7 days. The stents are used to protect the join between the ureters and the piece of bowel. A urostomy does not have any muscles therefore you have no control over the flow of urine. You will wear a urostomy bag over your stoma to collect your urine. Urostomy Night Drainage Bags feature a Non Return Valve to stop over flow back should the bag become full.Both bags feature a tap at the bottom for emptying the contents.


Differences between types of stomas