Food Challenge

What is a food challenge?
How do you get ready for the test?
What is done during the test?
How long will the test take?
How do you get to your test?

What is a food challenge?

Your doctor has suggested you/your child have a food challenge as part of the evaluation at National Jewish Health.  This is based on you/your child’s history and allergy test results.  A food challenge is done to help identify an allergy to a specific food and the amount of that food it may take to cause a reaction.

Learn reasons to do food challenges


How do you get ready for the test?

Please follow these directions when getting ready for this test: 

  • Your doctor may ask you to bring in a specific food for the food challenge.  Please bring the food the morning of the test.  If your child is having a food challenge, you may also be asked to bring a favorite food in which to place the food to be challenged.
  • Antihistamines will affect the results of some of these tests and need to be stopped before the testing is done.  If you have any concerns about stopping antihistamines check with your/your child's doctor before you stop the medicine.  We may not be able to perform the test If this medicine is not stopped.
  • Use the table below to determine which antihistamines to stop, and for how long, before your appointment at National Jewish Health.
Stop these oral antihistamines for 5 days before your appointment:
  • Claritin® (Loratadine)
  • Clarinex® (desloratadine)
  •  Allegra® (Fexofenadine)
 Stop these oral antihistmanines for 3-4 days before your appointment:
  •  Actifed® (Brompheniramine)
  •  Dimetapp®  (Brompheniramine)
  •  Atarax® (Hydroxyzine)
  •  Vistaril® (Hydroxyzine)
  •  Benadryl® (Diphenhydramine)
  •  Chlortrimeton® (Chlorpheniramine)
  •  Phenergan® (Promethazine)
  •  Tavist® (Clemastine)
  •  Antihist® (Clemastine)
  •  Zyrtec®  (Cetirizine)
  •  Actifed® (Combination medicine)
  •  Aller-Chlor® (Combination medicine)
  •  Bromfed® (Combination medicine)
  •  Drixoral® (Combination medicine)
  •  Dura-tab® (Combination medicine)
  •  Novafed-A® (Combination medicine)
  •  Ornade® (Combination medicine)
  •  Poly-Histine-D® (Combination medicine)
  •  Trinalin® (Combination medicine)


If you are taking an oral antihistamine that is not listed, stop the medicine for 3-4 days before your appointment. If you are not sure if the medicine you are taking is an antihistamine ask your doctor.

 Stop this medicine the night before your appointment:
  •  Singulair® (montelukast)
  •  Accolate®  (zafirlukast)       


Stop these medicines the morning of your appointment:
  • Zyflo® (zileuton)
  • Tagamet® (cimetadine)
  • Zantac® (ranitidine)
  • Pepcid® (famotidine)
  •  Axid® (nizatidine)


Sometimes antidepressants can also act as an antihistamine.  Let your doctor know if you are on any antidepressants before your food challenge.

Continue to take all your other medicine as you usually do.


What is done during the test?

During a food challenge, you/your child will start by eating a small amount of the suspected food. You/your child will receive increasing amounts of the food every 30 to 60 minutes until a normal meal-sized portion is eaten or the challenge is stopped because of symptoms or a reaction.  You/your child will be monitored closely during the food challenge by the nursing staff.  Your doctor will be available to provide evaluation or treatment in case of any symptoms.  
The food challenge may be an open, hidden or a double blind placebo food challenge.  During an open food challenge you/your child will know the food being challenged.  During a hidden food challenge the food may be hidden in a food you/your child likes.  This is helpful for a child who may not want to eat the food being challenged.  For example, if egg is the food being challenged, it may be hidden in chocolate pudding.   During a Double Blind Placebo Controlled Food Challenge the food being challenged is hidden from the person being challenged and the healthcare provider giving the food.  The healthcare provider preparing the challenge food is aware of the food being challenged.  This may be done to prevent the possibility of symptoms caused by thinking about eating a particular food.

Once the food challenge is done your doctor will discuss the results with you and make recommendations.


How long will the test take?

A food challenge will take from 4-8 hours. If a child is having the food challenge a parent will need to be present for the duration of the food challenge.


How do you get to your test?

Adults – Your food challenge will be scheduled in the Adult Triage Unit.  On the day of your scheduled test, report to Admissions. Both are located on the first floor of the Gaulter Building.  If you are an adult patient and have questions please call 303-398-1958.

Children – You/your child’s food challenge will be scheduled either in the Pediatric Clinic or Pediatric Care Unit.  Both are located on the second floor of the Gaulter Building.  If you have questions please call 303-398-1691.

Get directions to and view a campus map of National Jewish Health.


This information has been approved by Dan Atkins, MD  (November 2005)