Q: How often should allergy testing be done?
A: Allergy testing should be done initially, and then when indicated. Indications may be:
- A change in disease patterns
- A decision that something was missed on the original tests
- Probably when changing to different areas and different physicians
- After 3-5 years of immunotherapy that has been successful, or
- When making a decision about stopping immunotherapy.
Q: I recently underwent a scratch test to determine what I’m allergic to. The results of all 45 allergens they tested were negative (with the exception of the histamine control), although I clearly have seasonal allergies. Is it so important that I learn the cause of the allergies, or should I just go ahead with the treatment that works (a combination of antihistamine and nose spray)? Are there panels of less common allergens available for scratch tests?
A: There are over 50,000 species of mold in air. You were undoubtedly not tested for all of those. The same is true for pollens and other allergens. The skin testing that normally is done is for the most common things. Many things are less common or even unknown. If you were negative to the 45 allergens then you probably have either a sensitivity to something else that is less common or you have nonallergic rhinitis that just seems like an allergy.
At any rate, you certainly can get on with treatment. A combination of nasal sprays, antihistamines and eye drops (if needed) should help. If not, there are other options that don't require knowledge of what you are allergic to. Ask your doctor for advice.