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Stool Tests for Colorectal Cancer

How To Prepare continued...

Do not do the stool tests during your menstrual period or if you have active bleeding from hemorrhoids. Also, do not test a stool sample that has been in contact with toilet bowl cleaning products that turn the water blue.

Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).

How It Is Done

For a stool test, it may be helpful to catch the stool on some plastic wrap draped loosely over the toilet bowl and held in place by the toilet seat.

For tests that require more than one sample, be sure to collect each sample the same way.

FOBT

You will need to collect stool samples over three different bowel movements on three different days. The test kit includes a wooden applicator and test cards. Be sure to follow the instructions that come with your test kit, including any instructions to avoid certain foods in the days before the test.

Other ways to do FOBT:

  • Some kits instruct you to use a special cloth to wipe with after a bowel movement. After wiping with the cloth, you put the developer solution on it to check for color change that means there is blood in the stool.
  • Other kits have a special test pad that you place in the toilet after having a bowel movement. The pad will change color if the stool has blood in it.

If there is blood in your stool, call your doctor as soon as possible.

FIT/iFOBT

You will need to collect two stool samples for testing over different days. The test kit includes brushes and test cards. Be sure to follow the instructions provided in the test kit. The FIT/iFOBT test doesn't require a special diet in the days before you take the test.

Stool DNA test

For this test, you will save all the stool from one bowel movement. You use a special box for the stool and mail it to a lab. You will receive a kit from your doctor with supplies and instructions for doing this test at home. Always follow the instructions in your kit.

WebMD Medical Reference from Healthwise

Last Updated: October 30, 2013
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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