A Hydrogen Breath Test (or HBT) is used as a clinical medical diagnosis for people with irritable bowel syndrome, and common food intolerances. The test is simple, non-invasive, and is performed after a short period of fasting (typically 8 hours). Diagnosis (from the Greek words dia = by and gnosis = knowledge) is the process of identifying a disease by its signs, symptoms and results of various diagnostic procedures. ... The term non-invasive in medicine has two meanings: A medical procedure which does not penetrate or break the skin or a body cavity, i. ... Fasting is the act of willingly abstaining from all food and in some cases drink, for a period of time. ...

Tests vary from country to country, so the following information is provided as a rough guide to typical uses of the hydrogen breath test:

Fructose malabsorption - the patient takes a base reading of hydrogen levels in his/her breath. The patient is then given a small amount of fructose and / or sorbitol (typically 20 to 25mg), and then required to take readings every 15 to 30 minutes for two to three hours. If the level of hydrogen rises to 20 points or more above the base reading, and is sustained for at least two readings, then the patient has fructose malabsorption. Fructose malabsorption is a condition in which the fructose carrier in enterocytes is deficient. ... Fructose is a simple sugar (monosaccharide) found in many foods and one of the three most important blood sugars along with glucose and galactose. ... Sorbitol, also known as glucitol, is a sugar alcohol the body metabolises slowly. ...

Lactose intolerance - the patient takes a base reading of hydrogen levels in his/her breath. The patient is then given a small amount of pure lactose (typically 20 to 25mg), and then required to take readings every 15 to 30 minutes for two to three hours. If the level of hydrogen rises to 20 points or more above the base reading, and is sustained for at least two readings, then the patient has lactose intolerance. Lactose is a disaccharide that makes up around 2-8% of the solids in milk. ...

Lactulose intolerance - the patient takes a base reading of hydrogen levels in his/her breath. The patient is then given a small amount of pure lactulose (typically 20 to 25mg), and then required to take readings every 15 to 30 minutes for two to three hours. A particular spike pattern is required to be diagnosed with lactulose intolerance, with the earlier spike caused by the bacteria in the small intestine and a later one caused by the bacteria in the colon. Lactulose chemical structure Lactulose (Generlac®, Cholac®, Constilac®, Enulose®, Acilac®) is a synthetic sugar used in the treatment of constipation and liver disease. ... Lactulose chemical structure Lactulose (Generlac®, Cholac®, Constilac®, Enulose®, Acilac®) is a synthetic sugar used in the treatment of constipation and liver disease. ...

The excess hydrogen is typically caused by an overgrowth of otherwise normal intestinal bacteria. Gut flora, or intestinal bacteria, are the bacteria that normally live in the digestive tract and perform a number of useful functions involving digestion for their hosts. ...

External links

• Hydrogen Breath Test information from MedicineNet.
• Hydrogen Breath Test information from the University of Michigan Health System
• Hydrogen Breath Testinformation from the GP Notebook