Hydrogen Breath Tests

Hydrogen breath tests are performed at Marin General Hospital by registered nurses who are specialists in gastroenterology procedures. The procedure takes about 3 hours. It involves swallowing a sweet tasting liquid followed by the collection of breath samples that are later analyzed for hydrogen content. Preparation requires taking nothing to eat or drink for 12 hours before the test. The test is done to diagnose lactose intolerance or when a condition called small intestinal bacterial overgrowth is suspected.