What Is a Bowel Obstruction?

Bowel Obstructions Are Treatable But Can Be Life-Threatening

In This Article

Stomach with and without hernia

A bowel obstruction is the condition that occurs when a section of the bowel (either the small or the large intestine) becomes totally or partially blocked, so that stool cannot pass through it. Bowel obstructions can happen to just about anyone, but they are a common complication for people who have Crohn's disease.

In most cases, an obstruction can be treated without surgery. It may not always be possible to avoid an obstruction. However, people that are prone to them should work with a gastroenterologist to come up with a plan to try and avoid them and to talk about any treatments that can be done at home to relieve the symptoms.

Mechanical Bowel Obstructions

In a mechanical bowel obstruction, the stool is physically blocked from moving through the intestine, much like household plumbing may be blocked. A blockage could be caused by:

  • Hernia
  • Scar tissue (adhesions)
  • Impacted stool
  • Gallstones
  • Tumor
  • Abnormal tissue growth
  • Intussusception (a section of the bowel slides into itself, similar to when a telescope is closed)
  • Twist or kink in the intestines (volvulus)
  • Ingested foreign body (swallowing a nonfood item)


An obstruction is a serious condition and may need to be treated in the hospital. In some cases, the treatment is decompressing the intestine. This is accomplished by inserting a nasogastric (NG) tube through the nose and down into the stomach, which alleviates abdominal distention and vomiting. If inserting the NG tube does not help in relieving the blockage, surgery may be the next step. Surgery may also be needed if some of the tissue in the intestine has died as a result of the blockage.


If not treated, a bowel obstruction could lead to more serious problems, such as the death of some bowel tissue. If part of the bowel dies, it could result in an infection or in gangrene. A perforation (or hole) in the intestine is another possible complication of a bowel obstruction. A perforation is a medical emergency and will require immediate surgery.


An obstruction can cause the complete absence of stool or gas (known as obstipation), because no stool can physically pass through the blocked intestine. However, the obstruction could also result in a case of diarrhea, because only liquid stool will be able to pass beyond the point of the obstruction. Other symptoms of an obstruction are intense pain and cramping, abdominal fullness, and abdominal bloating.

The symptoms of a bowel obstruction are:


The diagnosis of a bowel obstruction is made through both a physical exam and diagnostic tests.

Bowel sounds: The bowel normally makes some sounds, such as gurgling and clicking, which can be heard at irregular intervals through the use of a stethoscope placed on the abdomen. If an obstruction is present, a health care provider may instead hear high-pitched sounds while listening to the abdomen. If the obstruction has been present for some time, there may be a complete absence of any bowel sounds.

X-Ray (abdominal radiograph): This is normally the first test that is used to determine if there is an obstruction. It is a non-invasive test that can be done relatively quickly. A radiologist or other specialist can use the x-ray film to determine if the signs of a bowel obstruction are present.

Barium enema: In the past, a barium enema was used to find the location of the obstruction. This method, however, is not always the best choice for showing whether an obstruction is caused by something pressing on the bowel (such as a tumor).

Upper GI with small bowel series: Much like the barium enema, this test was used to help pinpoint the obstruction, especially if it was in the upper gastrointestinal tract. This test is almost never used for diagnosis anymore.

Abdominal CT scan: This is the primary test that is used to diagnose bowel obstruction. Abdominal CT scans are done much like x-rays, except that sometimes contrast solution must be administered to the patient by mouth, enema, or IV. The benefits of the CT scan are that it can help find the location of the obstruction as well as what may be causing the blockage.


Some causes of obstructions are not preventable, such as those where there is no mechanical reason for the obstruction. In cases where the obstruction is caused by another condition, such as a tumor or a hernia, treating the underlying problem can help prevent the development of an obstruction.

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Article Sources
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  • A.D.A.M. "Intestinal obstruction." A.D.A.M., Inc 23 Jul 2008. 30 Jul 2009.