Bacterial Overgrowth in the Small Intestines

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What is Bacterial Overgrowth?

The main function of the small intestines is to absorb nutrients and digest foods. Typically we all have normal bacteria in the small intestines that help with digestion. The bacteria in the small intestines are not the same type normally found in the large intestines. Bacterial overgrowth occurs when there is an abnormally large amount of bacteria in the small intestines or bacteria from the large intestines regurgitates into the small intestines. The increased amount of bacteria or the abnormal bacteria invading the small intestines from the large intestines causes the production of gas such as hydrogen or methane. This gas causes abdominal pain, excessive gas, abdominal distention, or diarrhea.

What Causes Bacterial Overgrowth:

Conditions that delay the digestion of foods in the small intestines can increase the risk for developing bacterial overgrowth by giving normal bacteria time to reproduce in order to compensate for the slow digestion. This process can also cause the normal bacteria that is found in the large intestines to regurgitate into the small intestines, therefore causing abnormal bacteria in the small intestines.

Some medical conditions that can increase the risk of bacterial overgrowth:

• Chronic constipation • Diabetes • Gastroparesis • Diverticulosis

• Scleroderma • Small bowel obstruction • Crohn’s disease.

The Hydrogen Breath Test: Testing for Bacterial Overgrowth

A simple breath test can be done in the office to test for bacterial overgrowth. The overproduction of gasses such as hydrogen is absorbed through the bloodstream and excreted through the lungs. After you blow through a special device, the Hydrogen Breath Test can allow us to measure the amount of hydrogen in your lungs. An elevated hydrogen level alerts us to the possibility of bacterial overgrowth.

You must fast for 12 hours before your appointment. We ask that you take your medications as directed with a small sip of water the morning of the procedure. Please advise your health care provider if you are diabetic or if you have been on antibiotics within the last two weeks. You will be given a small amount of lactulose to drink. A random breath test will then be obtained and you will be asked to return to the office in one hour. Breath tests will then be obtained at 15 minute intervals over a three hour period. (You will need to allow for ample time to complete this test.) Detailed instructions will be provided at the time of the appointment.

Treatment for Bacterial Overgrowth in the Small Intestines

Antibiotics and probiotics are used to treat bacterial overgrowth.

Antibiotics treat infections caused by bacteria, and are usually taken for 7 days. You should alert your physician if you are allergic to any medications before taking any new medications and alert your physician if you have any side effects from new medications such as a rash, fever, diarrhea, nausea, vomiting, chest pain, or shortness of breath.

Probiotics are live microorganisms that are normally found in the small and large intestines.  The microorganisms help to regulate the normal flora in our intestines. Probiotics can be found at many health food stores or pharmacies and in certain foods we eat such as specially labeled yogurts.

If you think you might have bacterial overgrowth in the small intestines, please consult with one of your physicians.