Welcome to our new website!

Welcome! We hope you find our new website helpful and easier to navigate. It's now as easy to use on your smartphone as your desktop. Take a tour and please tell us what you think.

Breath Hydrogen Test: How to Prepare

Important information

  • Your test will begin at 7:45AM on the day that it is scheduled.
  • If you use antibiotics within four weeks of the test, it will need to be rescheduled.
  • If you performed colonic cleansing for a scope, the test will need to be rescheduled.
  • Stop probiotics, prokinetics (e.g. metoclopramide, domperidone) 24 hours before the test, and laxatives (e.g. Restorolax, Senokot, lactulose, fleet enema, docusate sodium), 24 hours before the test.
  • If you test positive the clinic will contact you with further instructions.

Please do not eat anything other than the list of acceptable foods.

Prepare food without any oils, butter, sauces, buns, or breading. If this diet is not followed, we may not be able to complete the test. You can use a bit of salt and pepper only.

Acceptable foods

  • Plain beef, chicken, pork, fish, tofu, poached or boiled eggs (no sauces or marinades)
  • White bread, white pasta, and white rice (ensure there is NO added fiber in all products)
  • Vegetables (must be peeled): carrots, zucchinis, peppers, potatoes and peeled cucumbers
  • Fruit: oranges, cantaloupe and ½ cup of tomatoes

To drink:

  • Unsweetened rice milk
  • Water

Acceptable foods

  • Plain ground beef, plain skinless chicken or turkey breast, plain tofu
  • Boiled or poached eggs
  • Plain white rice

To drink:

  • Unsweetened rice milk
  • Water

Do not:

  • Eat anything
  • Drink fluids (except water)
  • Smoke (even secondhand smoke) or vape
  • Do any vigorous exercise

Do not:

  • eat breakfast
  • brush your teeth
  • chew gum
  • use breath mints

  • The test will take between 3 - 4 hours to complete.
  • First, we will provide you with mint mouthwash to gargle and clean your mouth.
  • Once you've provided a baseline breath, we will provide you with a solution of either lactose, fructose, or glucose. You'll have 5 minutes to drink this.
  • Then every 20 minutes - 30 minutes for the next 3 - 4 hours you will provide breath.
  • Please report any symptoms of bloating, vomiting or diarrhea to the nurse.

Do not:

  • Eat food
  • Drink fluids (water is ok)
  • Smoke or vape
  • Do any vigorous exercise
  • Sleep

Do not eat the following foods

Legumes
  • Chickpeas, lentils, beans, etc.
Whole grain products
  • Bran cereal, whole wheat bread, etc.
Vegetables
  • Spinach
  • Broccoli
  • Cauliflower
  • Cabbage
  • Brussels sprouts
  • Onions
  • Garlic
Fruits
  • Dried raisins
  • Prunes
  • Figs
  • Dried apricots
Other foods
  • Nuts and salads
  • Milk, almond milk, yogurt, cheese, creams
  • Butter, oils, and margarine
  • Ketchup, mustard, mayonnaise, gravy, soya sauce
  • Juice, coffee, and tea

Disclaimer 

These resources are for educational purposes only. If you have questions, speak with your health care provider.

Print as a PDF fact sheet

Have you registered for MyChart?

MyChart is a free, secure, online patient portal that connects patients to parts of their CHEO electronic health record, anywhere, at any time. 

MyChart