SIBO Testing

The SIBO Lactulose Breath Test used by the NUNM SIBO Lab is manufactured by Quintron. Breath tests for SIBO have been reported to have greater reliability and acceptability than the blood test. 1,2,3,4,5

The Lactulose Breath Test is a non-invasive test that involves the patient consuming lactulose, a synthetic disaccharide manufactured by VistaPharm. This disaccharide is poorly absorbed from the gastrointestinal tract of humans because we do not have any enzymes capable of breaking down this substance. This feature is an advantage over the Glucose breath test because the lactulose will travel virtually unchanged into the distal end of the small intestine, whereas glucose is digested or absorbed before it reaches this area. Thus, the lactulose breath test can detect bacterial overgrowth in the distal portion of the small intestine. Some doctors believe that this type of SIBO is more common than other types of SIBO.


  1. Davidson, P.; Robb, T.A. Value of breath hydrogen analysis in management of diarrheal illness in childhood: Comparison with duodenal biopsy. J. Ped Gastroenterol Nutr 1985 (Jun); 4(3):381-7
  2. DiPalma,A.; Narvaez, R.M. Prediction of lactose malabsorption in referral patients. Dig Dis Sci 1988 (Mar);33:303-7
  3. Douwes, AC, Schaap, C and van der Klei-van Moorsel, JM. Hydrogen breath test in school Arch Dis Child. 1985 (Apr);60(4):333-7
  4. Fernandes, J, ; Vos, C.E.; Douwes, C.; Slotema, E.; Degenhart, H.J. Respiratory hydrogen excretion as a parameter for lactose malabsorption in children. Amer. J. Clin Nutr. 1978 (Apr);31:597-602
  5. Newcomer, D; McGill, D.B.; Thomas, R.J.; Hofmann, A.F. Prospective comparison of indirect methods for detecting lactase deficiency. New Engl J Med. 1975; 293:1232-6
  6. Solomons, W. Evaluation of carbohydrate absorption: The hydrogen breath test in clinical practice. Clin Nutr J. 1984; 3:71-78