Hydrogen Breath Testing

What is Hydrogen Breath Testing?

A hydrogen breath test is used as a clinical, medical diagnosis for people with Irritable Bowel Syndrome (IBS) and common food intolerances, such as lactose or fructose. The test is simple, non-invasive, and is performed after a short period of fasting (typically 8–12 hours).

Even though the test is normally known as a "Hydrogen Breath Test," the test monitors for both hydrogen and methane.  Many studies have shown that some patients (approximately 35% or more) do not produce hydrogen but actually produce methane. Some patients produce a combination of the two gases. Other patients don't produce any gas, which are known as "Non-Responders." Some physicians believe that these individuals actually produce another gas, which has not been determined yet. In addition to hydrogen and methane, carbon dioxide is used in the patient's breath to determine if the breath samples being analyzed are not contaminated (either with room air or bronchial dead space air).

What is Hydrogen Breath Testing Used to Diagnose?

  • Fructose Intolerance

The patient takes a base reading of hydrogen levels in his/her breath. The patient is then given a small amount of fructose, and then required to take readings every 15, 30 or 60 minutes for two to three hours.

  • 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 20-25 grams), and then required to take readings every 15, 30 or 60 minutes for two to three hours.

  • Small Bowel Bacterial Overgrowth (SBBO)

​The patient is either given a challenge dose of glucose, also known as dextrose (75-100 grams), or lactulose (10 grams). A baseline, breath sample is collected, and then additional samples are collected at 15 minute or 20 minute intervals for three to five hours.