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The guidelines listed below are to be followed for all hydrogen breath tests:

  • Patients will be NPO (nothing by mouth) for 12 hours prior to the test.
  • No smoking, including second hand smoke for 12 hours prior to the test.
  • No sleeping or vigorous exercise for at least one hour before or during the test.
  • Recent antibiotic therapy or colonoscopies will affect these breath tests à please advise medical staff is any of the above pertain to you as soon as possible
    • No antibiotics 14 days prior to the test (Amoxicilin, Erthromycin, Xifaxan, Neomycin, etc.)
    •  No acid suppressing medication and Probiotic up to one day before the test (Dexilant, Prevacid, etc.)
    • Wait 30 days after colonoscopy procedure.
  • Neither mints nor gum chewing after midnight.
  • Brush your teeth in the morning (mint flavored toothpaste/mouth wash is acceptable)
  • You may take scheduled medications at least two hours prior to the study (as long as they are not antibiotics, acid suppressing medications or probiotics) with small sips of water, however, it is preferable that medications be taken after the study has finished.

If any of the above conditions have been compromised, the test will be rescheduled.

Listed below are generic avoidance groups and are not limited to what is listed. If you are unsure if something may affect the test, do not consume the product and consult with medical staff.

24 hours prior to the test, please avoid the foods listed below. Nothing to eat or drink 12 hours prior to the test.


  • Grain products: pastas, whole grain products, cereal or brans
  • Fruits: fruit juices, applesauce, canned fruits, raw and dried fruits like raisins, etc.
  • Vegetables: vegetable juices, potatoes, alfalfa sprouts, beets, carrots, celery, etc.
  • Vegetables from cruciferous family: broccoli, cauliflower, brussel sprouts, cabbage, beans, lentils, corn, etc.
  • Nuts, seeds or beans: all nuts, seeds, beans and foods that may contain seeds
  • All dairy products (except eggs): milk, cheese, yogurt, butter, ice ceram, etc.

Suggestions for the patient’s last meal to consume 24 hours prior to the test:


  • Baked or broiled chicken or turkey seasoned with salt or pepper only
  • Baked or broiled fish seasoned with salt and pepper only
  • Plain steamed white rice – no oil or butter
  • Eggs
  • Clear chicken broth


Gastroenterology Associates of Beverly Hills
8631 W. 3rd Street, Suite 815E
Los Angeles, CA 90048
Phone: 310-858-2224
Fax: 310-858-2225

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