Bowel transit time test

Bowel transit time tests may be done to:

• Find the cause of constipation or the slow movement of food through the digestive tract.
• See if one place in your intestines is slowing down movement more than the rest of your intestines.

Bowel transit time tests are not done to find the cause of diarrhea.

Your doctor will give you one or more gel capsules filled with markers that will show up on an X-ray. Follow your doctor's instructions about when to take the capsules. You may take only one capsule. Or you may be told to take one at a certain time for 2 or 3 days in a row. You will then have X-rays taken of your belly. These are usually done on day 5. The percentage of markers that show up on the X-ray tells your doctor if you have a normal bowel transit time.

You may need to change your diet for a few days before having this test. You may also need to stop taking medicines for a short time before having a bowel transit time test. Tell your doctor about all the prescription and nonprescription medicines you are taking.

Bowel transit time depends on what types of food you eat and how much you drink. Different people have different bowel transit times.