Hydrogen Breath Test

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A hydrogen breath test is done to see whether your child is able to digest and absorb certain sugars. The most common sugar tested is lactose, the sugar found in milk. Other sugars that can be tested include fructose, sucrose, lactulose and even starch. If your child is not able to digest the sugar, the body cannot absorb it. This may cause gas, crampy pain in the abdomen and diarrhea.

Hydrogen gas is produced from the unabsorbed sugar as it reaches the large intestine. This gas can be measured in your child’s breath. During the hydrogen breath test, breath samples are taken and sent to the lab to be checked for hydrogen.

How to Prepare for the Test

  • Your child should have nothing to eat or drink after 9 PM the night before the test.
  • He or she should not even have gum, mints or cough drops. If your child takes morning medicines, check with the nurse to see if the medicines should be taken.
  • No smoking, including second-hand smoke, for at least 1 hour before or at any time during the breath test.
  • No sleeping or vigorous exercise for at least 1 hour before or at any time during the breath test.
  • If your child recently had antibiotic therapy, runny diarrhea, colonoscopies, barium studies or enemas, please wait 14 days after he has finished any of these before starting the breath test.
  • Your child may brush his or her teeth but should not swallow the toothpaste. Have your child rinse the mouth well after brushing teeth.
  • The test does not hurt.
  • Explain the test to your child in a way he or she can understand.
  • If your child is old enough, you can help him or her practice for the test. You will need a noisemaker party favor. Have your child blow into the end of the noisemaker and try to hold the curly end out while you slowly count to 10.
  • The test will take 4 hours to complete. You may bring books, small toys or a game to entertain your child while the test is being done.
  • The day before the test:
    • Avoid eating foods like pasta, dairy products, whole grain products, bran, high fiber cereals, granolas, nuts, cabbage, onions, beans/peas/lentils, potatoes, fruit and fruit juices.
    • Foods your child can eat include baked or broiled chicken, fish or turkey (seasoned with salt and pepper only), white bread, steamed white rice, eggs, clear chicken or beef broths, peanut butter (smooth), pretzels, gelatin, table sugar, waffles/pancakes, Puffed Rice/Rice Krispies/Corn Flakes/Special K, soy or almond milk, plain cookies or cakes.
    • The last meal of the day should not be a large meal and should contain no fiber.

How the Test is Done

Hydrogen breath test

  • Your child will be taught by the nurse how to purse his or her lips around a plastic mouthpiece that is connected to the small foil collection bag (Picture 1).
  • When your child breathes out, the breath is collected in the foil bag. Then the child will drink the sugar solution.
  • Breath samples will be collected at certain times over the next 4 hours. Your nurse will tell you the times that each breath will be collected.
  • Your child may not eat or drink anything until the test is finished.

After the Test

  • Your child may eat and drink his or her usual foods after the test.
  • If your test was ordered by a GI practitioner at NCH, our office will contact you with the results. If you have not heard from us within 2 weeks, please contact us at 614-722-3450.
  • If your child was referred to us for the test, please contact the practitioner who referred him or her for results and follow-up.

If you have any questions, please ask your nurse or call the GI office.

Hydrogen Breath Test (PDF)

HH-III-63 12/85, Revised 8/16 Copyright 1985 Nationwide Children’s Hospital