2016-06-16 17:05:38 UTC

Constipation 104: Getting Tested

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If your doctor decides your constipation is bad enough, there are a few tests that can be done.


Common Tests

To start, your doctor may take samples of blood, urine and stool. 



Other Tests Your Doctor Might Do


  • X-Ray
    • An X-ray of your belly can be helpful to see if there is a large amount of stool inside your bowels due to constipation. 
  • Lower GI Endoscopy
    • A colonoscopy or sigmoidoscopy may help find diseases, like colon cancer or diverticular disease, in the rectum and colon. 
    • To get ready for this test, the bowel is emptied of stool with a clear-liquid diet and laxatives, usually the day/evening before. 
    • Once in the doctor’s office, hospital or outpatient center, you will be given medicine to block pain and make you feel relaxed and sleepy.
    • Your doctor will place a long, thin (about the width of your little finger), flexible tube with a tiny camera on the end through the anus to look at the rectum and intestine.
    • To learn more about colonoscopy, click here.


Less Common Tests 


  • Colonic Transit Time
    • This test can be done to find out how long it takes for stool to move through your colon.
    • For the test, you swallow a pill with about 24 tiny pellets or markers that scatter in the large intestine. 
    • After a few days, one or two X-rays are taken to see how many pellets are still in your system. 
    • There are many ways to do this test, and your doctor will decide which is best for you.
  • Anorectal Motility Study
    • If your doctor thinks you might have pelvic floor dysfunction (for example, if you strain a lot or feel unsatisfied after going to the toilet), this test is done. 
    • For this test, a small tube is placed in the rectum, and you are asked to contract and relax the muscles while the data of how you use your muscles is tracked
    • In addition, you may be asked to expel (push out) a balloon from the rectum.
Constipation – What To Know:
  • Constipation can often be managed through changes in diet, drinking more fluids and exercise.
  • Know what is normal for you. A bowel movement is not needed every day.
  • Tell your doctor if your constipation does not go away or keeps coming back.


© AGA, September 2017

©AGA, July 2016

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