A Sucrose Hydrogen Methane Breath Test (SHMBT) is a test that is easy to do at home and can provide valuable information on what is going on in your digestive system. It is non-invasive, which means that you don’t need to give blood or a tissue sample.

If you are suffering from unexplained and persistent diarrhea, abdominal pain, and/or a lot of gas, your healthcare provider (HCP) may order a SHMBT. This test can aid in the diagnosis of Congenital Sucrase-Isomaltase Deficiency (CSID), a type of Sucrose Intolerance. CSID is a relatively-rare genetic condition in which the proteins needed to break down sucrose, or table sugar, into usable energy for your cells is not working properly. NOTE: The SHMBT requires drinking a large amount of sucrose that may cause gastrointestinal symptoms, some of which may be severe if you have CSID.

The SHMBT typically takes about three hours. You will collect breath samples in seven glass tubes. The first tube will be used to collect your breath after you have not had anything to eat or drink (other than water) for 12 hours. Then you will mix a predetermined amount of sucrose (table sugar) with water and drink it. You will then collect breath samples every 30 minutes to measure whether sucrose is being digested normally after drinking the sugar water.

There are some important things to keep in mind before taking a SHMBT. The breath test company will provide detailed instructions to help you do the breath test correctly. Paperwork inside the SHMBT will also provide you with a phone number should you need telephone support. Although each company’s SHMBT instructions may vary, there are some common rules you need to know.

*Stop taking probiotics for at least four to five days before taking the test. You may be managing your stomach issues with probiotics, but probiotics will affect the SHMBT results.

*Stop taking antibiotics.

*There is a special diet that needs to be closely followed between 12 and 24 hours before the test. The instructions will usually tell you a list of allowed foods. Eating the wrong foods will give inaccurate test results.

*12 hours before you take the test, you cannot eat or drink anything except water.

*Before starting the SHMBT, brush your teeth since the bacteria in your mouth could affect the test.

*Do no smoke, sleep, or exercise 1 hour before the test or at any time during the test. These activities can affect the test results.

*Always consult with your healthcare provider before stopping any medications or altering your diet.

The results of the SHMBT can help your healthcare provider understand if your stomach issues are related to how your body responds to sucrose.