What is a bowel obstruction?

Bowel obstruction (also called intestinal obstruction) is when something blocks the normal movement of food and liquids through your bowel (intestines). It can happen for a number of reasons.

There are different types of bowel obstruction. A blockage in your digestive system can be:

• in the small intestine or the large intestine
• partial (meaning your bowel is partly blocked and some faeces (poo) can still get through) or complete (meaning it is fully blocked and not even gas can get through)
• simple (just a blockage) or complicated (meaning the blockage has cut off your bowel's blood supply and caused damage to your bowel)

What are the symptoms of a bowel obstruction?

The symptoms of a bowel obstruction depend on where the blockage is and the cause.

Small bowel obstruction

Symptoms of a small bowel obstruction can start quickly. You may notice:

• cramping abdominal pain, especially in your upper abdomen and around your belly button
• inability to pass gas or bowel motions
• vomiting
• diarrhoea — if your bowel is only partially blocked

If your pain is severe and constant, this may mean the blockage is affecting the blood supply to your bowel.

Large bowel obstruction

Symptoms of a large bowel obstruction usually start gradually and may be less severe. You may notice:

• constipation that gets worse, until you can't pass any bowel motions or gas
• bloating
• cramps in your lower abdomen
• vomiting — this is uncommon and may start after the other symptoms

However, in some cases a large bowel obstruction can cause sudden constant pain. It depends on what is causing the obstruction.

When should I go to the emergency department?

Go to the emergency department straight away if you have abdominal pain and are unable to pass bowel motions or gas (wind).

What should I do before I get to the emergency department?

It's important not to have anything to eat or drink before a doctor examines you in the emergency department.

What causes a bowel obstruction?

There are many potential causes of a bowel obstruction. Depending on your age and medical history, you might be more likely to develop certain types of bowel obstruction.

In adults, the most common causes of bowel obstruction are:

• adhesions — these are scars of tissue that can form between organs that shouldn't be connected. The bowel can twist around the scar creating a knot around your intestine. Adhesions usually form after abdominal or pelvic surgery.
• bowel cancer
• hernias

Other causes include:

• inflammatory bowel disease, such as Crohn's disease or Ulcerative Colitis
• diverticulitis
• volvulus — when part of the bowel twists around itself
• intussusception — when part of the bowel folds in on itself (more common in babies and young children)
• a foreign body, such as a swallowed object or gallstones
• severe constipation

What is a pseudo-obstruction?

This is different type of bowel obstruction, which is also known as a functional bowel obstruction. It happens when your bowel muscles are not contracting properly and can't push faeces along effectively, even though there is no physical blockage.

It causes the same symptoms as a mechanical (physical) bowel obstruction.

Possible causes include:

• abdominal surgery
• injuries
• a muscle or nerve disorder
• abdominal infection
• some medicines, such as opioids
• low potassium

How is a bowel obstruction diagnosed?

To diagnose bowel obstruction, your doctor may:

• ask you questions about your health and symptoms
• examine your abdomen
• refer you for blood tests
• refer you for x-rays or a CT scan of your abdomen

How is a bowel obstruction treated?

Treatment for bowel obstruction depends on the cause. You will usually need treatment and monitoring in hospital. If you think that you may have bowel obstruction don't eat or drink and go immediately to your nearest hospital.

While in hospital, you might have the following treatment:

• Your urine output may be monitored.
• You may get fluids through an intravenous (IV) drip.
• You may receive pain relief and anti-nausea medicines.
• A nasogastric tube may be inserted through your nose and down into your stomach (but usually only if you have severe bloating or vomiting).
• You may have procedures such as a colonoscopy or sigmoidoscopy.
• You may need to have surgery.

Some people need to have surgery immediately. Some people are treated with IV fluids and medicines for 2 or 3 days and then have surgery if they are not getting better. Other people don't need surgery at all. Your doctor will discuss the likely cause of your bowel obstruction and the options for treatment.

If your obstruction is caused by bowel cancer, you might need surgery to remove the affected part of your bowel.

What are the complications of a bowel obstruction?

If your bowel stays blocked, it could lead to:

• reduced blood supply to part of your bowel, leading to permanent damage
• perforation (a tear in the wall of your bowel)
• sepsis
• death

Can bowel obstructions be prevented?

Many types of bowel obstruction aren't preventable, but there are things you can do to lower the chance of your bowel becoming blocked.

Diet

If your gut is healthy, a high fibre diet is good for you. However, if you know that parts of your bowel are narrowed, you should follow a diet low in insoluble fibre. Insoluble fibre is the hard and rough part of plants that we eat, such as fruit and vegetable skin, whole grains and some nuts and seeds. This type of fibre can get stuck in narrow parts of the bowel.

You can avoid insoluble fibre by:

• peeling, cooking or finely cutting up fruit and vegetables and removing their seeds
• eating white bread, pasta and rice rather than wholegrain
• avoiding nuts and seeds

This type of diet can increase your risk of constipation. To prevent this, make sure to drink lots of water and get some exercise. Talk to your doctor about whether you might benefit from a laxative medicine.

Also, it is important to cook your food well, avoid tough and stringy food and chew well before swallowing.

It may be helpful to discuss your diet and nutrition with a dietitian.

Preventing causes of bowel obstruction

There are ways to prevent some of the causes of bowel obstruction.

You can lower your risk of bowel cancer by:

• avoiding smoking
• including dairy products, whole grains and fibre in your diet and limiting red meat and processed meats
• maintaining a healthy weight
• getting 30 minutes of exercise every day
• limiting alcohol to less than 2 drinks a day
• having screening tests for bowel cancer

If you have a bowel condition such as Crohn's disease, it is important to follow your doctor's instructions to help manage the condition.

Resources and support

If you are concerned about bowel cancer, find out here about how to get a bowel screening test kit. You can also visit Bowel Cancer Australia for more information.

Call healthdirect on 1800 022 222 at any time to speak to a registered nurse (known as NURSE-ON-CALL in Victoria) for more information and advice.

Do you prefer to read in languages other than English?

For more resources in languages other than English, you can find more information here:

• Constipation
• Healthy diet and bowels
• Watch the video: Do the bowel home screening test. It could save your life

Looking for information for Aboriginal and/or Torres Strait Islander people?

Find videos and information about bowel cancer screening for Aboriginal and/or Torres Strait Islander people provided by the Australian Government Department of Health and Aged Care.