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 breath hydrogen clinic nurse will discuss the plan for management.

The Preparation Diet

The Day Before | 6AM to 4PM

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

The Evening Before | 4PM to 8PM

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

The Night Before | 8PM onward

Do not:

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

Morning of the Test

Do not:

eat breakfast
brush your teeth
chew gum
use breath mints

What to Expect During the Test

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

Restricted Foods

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 seeds
Milk, almond milk, yogurt, cheese, and creams
Butter, oils, and margarine
Ketchup, mustard, mayonnaise, gravy, and soya sauce
Juice, coffee, and tea

Contact us with any questions or concerns. If you need to reschedule the appointment or cancel, please contact the breath hydrogen line at 613-737-7600 ext. 1538. You can also reach the nurse directly through MyChart.

Disclaimer

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

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