Other Important Information for Patients

Diabetes and Breath Testing


  • Patients with diabetes should be given appointments first thing in the morning. Please let the receptionist know if you are diabetic upon booking.
  • As breath testing involves a change in diet for the day before each test, patients with diabetes who normally monitor their capillary blood sugar should do so more frequently for 24 hours before and after breath testing. Please bring your capillary blood sugar testing equipment with you.
  • If in doubt, patients should either contact their endocrinologist or diabetes nurse specialist.

For Patients who are Diet-Controlled Diabetics

  •  No specific changes in the breath test protocol are necessary.

For Patients who are taking Oral Hypoglycaemic agents

  • Diabetes medication should be omitted on the morning of the test. After the test, patients should revert to their normal treatment regimen.

For Patients taking Insulin

  • Please bring your usual insulin and syringes with you.

Negligible Lactulose Testing

At our Breath Testing Centre, we believe it is imperative to conduct a lactulose breath test as a baseline measurement.  Because lactulose is poorly absorbed by everyone, we can assess the type of intestinal gas produced by a patient (hydrogen or methane) to compare the response with other tested sugars and to evaluate gut transit time or evidence of small intestinal bacterial overgrowth if requested.

It should be noted however, that some patients will produce a negligible response to the lactulose sugar indicating that they may be a low, or non-hydrogen/methane producer. Results from our patient records over the past years indicate that this will happen in around 10% of patients and may be caused by the use of antibiotics, probiotics, bowel prep (as for colonoscopy), slow transit time or, unknown reasons.

We do request our patients to cease any antibiotics or probiotics two weeks prior to testing, and that they do not have a colonoscopy four weeks prior. Our records indicate that approximately 70% of patients classified as ‘low’ or ‘ non-hydrogen/methane producers’ on lactulose will show significant readings on other sugars tested. However, for those that do not, breath testing is unhelpful and dietary manipulation is recommended by an experienced dietitian to manage symptoms in these patients.

We do inform the patient at the time of a negligible lactulose test that this has occurred, notifying them that in 70% of cases, they will have reliable results for following tests, and giving them the option to cancel the other tests if they wish before proceeding. We find that most patients do decide to continue to see what is shown. This information highlights the importance of conducting a lactulose breath test on each patient before continuing onto the other tests required.

More Information