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Hydrogen Breath Test

The hydrogen breath test helps to determine if certain conditions or diseases are affecting your intestinal tract, such as Small Intestinal Bacterial Overgrowth (SIBO). Your body produces hydrogen and/or methane gas during digestion, which can cause bloating, abdominal discomfort and sometimes diarrhea or constipation. The gases absorbed by the intestines enter the bloodstream where they are transported to the lungs. Exhaling releases these gases. By analyzing the gases contained in your breath when you exhale, we can check for specific conditions and begin appropriate treatment.

What is Small Intestinal Bacterial Overgrowth (SIBO)?

Small Intestinal Bacterial Overgrowth (SIBO) is overabundant bacteria that exists in the small intestine. The hydrogen breath test looks for bacterial overgrowth, or intolerances to lactose or fructose.

  • Lactulose is poorly absorbed in the gastrointestinal tract, making it ideal for testing bacterial overgrowth throughout the small intestine.
  • Lactose and fructose intolerance occur when an individual has deficiency in enzymes needed for absorption. Normally, lactose and fructose are broken down in the small intestine, absorbed, allowing only small amounts of lactose or fructose to reach the colon. If they reach the colon in raw form, lactose and fructose are digested by bacteria producing a large amount of gas, which can be measured in the breath sample.

What can I expect from a hydrogen breath test?

This test requires that you drink a mixture of either lactulose, lactose or fructose in water. For this test, you will drink the specified mixture given to you and then give a breath sample every 15 – 20 minutes over a three-hour period.

Hydrogen breath test
Hydrogen breath test

We offer this test at our North Haven Endoscopy Suite.