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  • Pediatric Gastroenterology, Nutrition, and Liver Diseases

  • Lactose Testing

  • What is lactose intolerance?

    A person who is lactose intolerant has symptoms that are caused by his or her inability to absorb lactose. Lactose is the sugar (carbohydrate) that is in milk and milk products. If a sugar is not absorbed, it is passed into the lower intestine and broken down by bacteria. When the sugar is broken down, it produces a hydrogen gas. The hydrogen is absorbed into the bloodstream and then eliminated through a person's breath.

    What is a Hydrogen Breath Test?

    The Hydrogen Breath Test is used to determine if a patient is unable to absorb a particular type of sugar. The test measures the amount of hydrogen produced from the unabsorbed sugar. If the hydrogen levels are elevated, this indicates the sugar is not being absorbed. The breath test can be used to diagnose lactose, sucrose and fructose malabsorption and bacterial overgrowth.

    How do I prepare for a Hydrogen Breath Test?

    You will be asked to fast for 12 hours before the test. Fasting means eating no food, medications, chewing gum or drinking beverages. The day before the test you should not eat any gas-producing foods such as peas, beans, broccoli or cauliflower. You should not take any antibiotics for 7 days prior to the test. No smoking is permitted for 12 hours before the test.

    What happens the day of the test?

    After you arrive and register at the Division of Pediatric Gastroenterology at Hasbro Children's Hospital in the Lower Level (LL) of Hasbro Children's Hospital the nurse who administers the test will ask you some questions. You will then be asked to breathe into a collection bag to gather a sample of your breath. Then you will be given a cup of sugar solution to drink. Breath samples will be collected and analyzed every 30 minutes for approximately 2½ hours.

    When will I learn the results of the test?

    A gastroenterology physician interprets the test results. They are then sent to your primary physician who will notify you of the results.