Motility Diagnostic Procedures
Breath Hydrogen Study
Call 415-600-3676 to register by phone within five (5) days of your appointment.
Please Check in 15 minutes before your appointment at:
California Pacific Medical Center
2333 Buchanan St. 5th floor GI Lab
San Francisco, CA 94115
Please bring your insurance card(s).
- Two (2) Weeks PRIOR to your Procedure: please STOP taking Antibiotics(Erythromycin, Flagyl, Cipro, Xifaxan, etc) or Probiotics(Align, VSL#3, Yogurt, etc).
- Six (6) Hours PRIOR to your Procedure: please STOP Eating (including mints, gums, hard candy, etc.), you may Drink Clear Liquids only.
- Three (3) Hours PRIOR to your Procedure: please STOP Drinking all fluids at this time.
This procedure will take approximately 3 hours. No sedation will be given and you will not need a driver to take you home.
What is the hydrogen breath test?
The hydrogen breath test is a test that uses the measurement of hydrogen in the breath to diagnose several conditions that cause gastrointestinal symptoms. In humans, only bacteria - specifically, anaerobic bacteria in the colon - are capable of producing hydrogen. The bacteria produce hydrogen when they are exposed to unabsorbed food, particularly sugars and carbohydrates, not proteins or fats. Although limited hydrogen is produced from the small amounts of unabsorbed food that normally reach the colon, large amounts of hydrogen may be produced when there is a problem with the digestion or absorption of food in the small intestine, that allows more unabsorbed food to reach the colon.
Large amounts of hydrogen also may be produced when the colon bacteria move back into the small intestine, a condition called bacterial overgrowth of the small bowel. In this latter instance, the bacteria are exposed to unabsorbed food that has not had a chance to completely traverse the small intestine to be fully digested and absorbed. Some of the hydrogen produced by the bacteria, whether in the small intestine or the colon, is absorbed into the blood flowing through the wall of the small intestine and colon. The hydrogen-containing blood travels to the lungs where the hydrogen is released and exhaled in the breath where it can be measured.
How is hydrogen breath testing performed?
Prior to hydrogen breath testing, you will be asked to fast for at least six (6) hours. At the start of the test, you will blow into a bag filling it completely with air. Depending on the purpose of your test, the nurse will then give you a test sugar (such as lactose, sucrose, sorbitol, fructose or lactulose) to drink. Then you will blow air into a bag every 15 minutes for one and a half or three hours. The test sugar gets broken down in your body and measurements of hydrogen and methane will be obtained from your breath samples.