Small Intestinal Bacterial Overgrowth (SIBO) 3 Hour - Breath (Genova Diagnostics)

Hydrogen (H2)

Optimal range: 0 - 20 ppm

Hydrogen increase over baseline by 90 minutes.

A rise of ≥ 20 ppm from baseline in hydrogen by 90 min should be considered a positive test to suggest the presence of SIBO


Methane (CH4)

Optimal range: 0 - 10 ppm

Utilization of breath methane levels for SIBO assessment is controversial largely due to a lack of validation related to diagnostic specifics such as timing and magnitude of increase; however, CH4 measurements are increasingly obtained to address other clinical questions. Recent evidence has associated CH4 production with the pathogenesis of common clinical conditions, such as obesity, irritable bowel syndrome (IBS), and constipation.