The basis of food allergy testing is very similar to environmental allergy testing, with some important exceptions. Intradermal testing is not done when evaluating for food allergy. Additionally, in food allergy using blood tests may be helpful in allergy diagnosis, and long-term management and prognosis.
Sometimes, a supervised oral challenge to the suspected food is required to remove or confirm a particular food as an allergen. We have conducted hundreds of such challenges in our office in a safe manner.
Food allergy requires a very nuanced understanding of the scope of the problem and a healthy open dialogue between the patient/family and physician.
Medications that Interfere with Allergy Skin Testing:
These medications interfere with allergy skin tests and SHOULD BE DISCONTINUED PRIOR TO TESTING:
Five days prior to testing, stop all over-the-counter allergy, cold and sleep medications (Allegra, Benadryl, Claritin, Clortrimeton, diphenhydramine, Zyrtec, etc.), and prescription antihistamines (Clarinex, Xyzal, etc.). This includes nasal sprays containing antihistamines, such as azelastine, Astepro, Dymista and Patanase.
- Older antidepressants like Elavil (amitryptyline) should be stopped three days prior to testing.
- Newer antidepressants (Prozac, Zoloft, etc.) do not interfere with testing.
Most medications do not interfere with skin testing and may be continued.
Do Not Stop The Following:
- Cortisone nasal sprays (fluticasone, Nasonex, Nasacort AQ, Rhinocort, Veramyst, etc.)
- Asthma medications (Albuterol, Flovent, Singulair, Advair, etc.)
- Eye drops for allergy (Patanol, Elestat, Zaditor, etc.)
- Decongestants (Sudafed, Sudafed PE, etc.)
- Oral steroids (Prednisone, Medrol, Prelone, etc.)
- Birth control pills
- Medicines for other conditions such as diabetes, arthritis, reflux, high blood pressure, etc.
We Do Not Perform Skin Testing on the Following Patients:
- Women should not be skin tested if they are or may be pregnant
- Patients taking beta blocker medications on a daily basis should not be skin tested or take allergy shots.
The use of beta blocker medications (which may be prescribed for high blood pressure, heart conditions, glaucoma, migraine prevention, etc.) may hinder the effectiveness of treating systemic reactions to allergy skin testing or immunotherapy. We will be unable to skin test patients who have been prescribed beta blocker medications, but these patients are eligible for allergy blood tests. Ask your pharmacist, prescribing physician or one of our nurses if you are not sure if your medication is a beta blocker. Discover More about Beta Blockers.