Blood Work While On Allergy Meds

[Staceyshoe]

Before I take my son in for bloodwork, I want to make sure that his allergy medication (Rx antihistamines for environmental allergies--Allegra) won't affect his results. Does anyone know? I'm going to try to get the testing through our pediatrician, and I'm not sure how knowledgable he is about celiac. TIA!

[Emilushka]

There shouldn't be any interaction. It's a different part of the immune system.

[jerseyangel]

Before I take my son in for bloodwork, I want to make sure that his allergy medication (Rx antihistamines for environmental allergies--Allegra) won't affect his results. Does anyone know? I'm going to try to get the testing through our pediatrician, and I'm not sure how knowledgable he is about celiac. TIA!

Antihistamines won't affect the Celiac blood testing at all.

(They would affect skin/blood testing for allergies but Celiac is not an allergy.)

[Emilushka]

To be more clinical about it, allergies (and antihistamines and anti-allergy medications) work on IgE antibodies and mast cells. These are the parts of the immune system that react to an allergen. They are pre-formed antibodies that combine with the mast cells to release histamine (hence the name of the antihistamine drug family) and trigger the allergic response. This is why they require some pre-exposure (so you get a huge, deadly reaction the SECOND time you're stung by a bee but not the first) and why they are so quick - you don't wait for the body to make antibody because it's already there.

Celiac disease and your gut mucosa use IgA and IgG antibodies. IgA antibodies are for the mucosal surfaces of your body (such as your gut) and IgG are overall memory antibodies that provide long-term immunity (like after a vaccine or infection).

So the allergy meds and gluten are using totally different arms of your immune system. As I posted before, that's the short version.

[Staceyshoe]

Thank you both! I've read so much about false negatives in the bloodwork, and I don't want to doubt the results after they come in. We did genetic testing so we know that my son has "THE" classic celiac gene combo, but he doesn't have the stereotypical symptoms. He's always had some kind of digestive problem, though, so I thought we'd do the bloodwork before we start a gluten-free diet. We'll see how the tests and the gluten-free diet go. Maybe it's completely unrelated to celiac. I just have a nagging suspicion about celiac though.