Do antihistimines make DH worse?

[greenbeanie]

Hi folks! For those with confirmed DH, do antihistimines make it worse? I'm trying to figure out an unpleasant puzzle. 

I've been strictly gluten free for over four years. It took a couple years of eliminating all processed foods for symptoms to resolve, but finally I've been feeling amazingly good for the past year. I have an official celiac diagnosis from a GI, and my daughter has biopsy-confirmed celiac, but my own diagnosis was on clinical grounds because I was unable to complete an adequate gluten challenge due to an awful reaction. I'd had an incredibly itchy DH-looking rash for over 30 years at the time of testing, but it was not biopsied because I'd been gluten free for months at that point. On a gluten free diet, the rash improved right away and mostly disappeared within the first year.

So...the mystery is that the rash has slowly come back in recent months. Nothing in my diet has changed. I cook almost all of my food from scratch, don't eat out, and mostly avoid iodized salt. The only medications I take are OTC antihistimines - the same gluten-free brands that I was previously taking with no problem. Weirdly, the antihistimines seem to make the rash worse! It flares up dramatically a few hours after taking it. But blood tests indicate that I am not having an allergic reaction of any sort (i.e., rash isn't caused by an allergic reaction to the drug or to environmental allergies). Obviously I can no longer tolerate antihistimines, but I'm trying to figure out why. ALL antihistimines worsen the rash - Allegra, Zyrtec, Claritin, Benadryl, children's dye-free liquid that has entirely different inactive ingredients, etc.

One thought is that I might have suddenly become more sensitive to trace gluten in the medications, even if they're listed as gluten free. Another thought is that maybe the mechanism that makes antihistimines work for allergies somehow worsens DH? Has anyone else experienced this? 

I've been referred to a very good dermatologist, and I'm sure he'll biopsy the rash. My appointment isn't until November, though. (I know a biopsy wouldn’t show DH after this long gluten free, but it might indicate or rule out other things.) 

[squirmingitch]

Hey greenbeanie!

Sorry it's taken so long to get any reply. I am in FL & hurricane Irma happened you know. NO damage here thank goodness but we did have power outage and then the internet went down & didn't come back up until today.

Weird, weird, weird! First, no, I haven't suspected antihistamines make my rash worsen. However, the only antihistamine I've taken in the last 4 or 5 years is Claritin reditabs. At a couple points in time, I did suspect possibly perhaps the Claritin was making the rash worse but subsequent uses proved that untrue. Or maybe it was true then & not later? Sometimes these things can be soooooo darn hard to nail down! 

So here's what I have to say about your dilemma. It's possible you've become so sensitive. It's also possible something like iodine is making it flare. Have you been eating a lot of "greens" lately? such as kale, spinach, turnip greens. I have found that asparagus is out for me as apparently it is high in iodine content. I tried 3 different times this year & each time I had asparagus, I had a flare. Eating more seafood than usual? Lots of cheeses & dairy? it's also possible you could have developed another food intolerance. Celiacs who do not have the rash, get reactions just as if they have been glutened even though they haven't, so why wouldn't the same apply to us? Right down to making the rash flare. I wonder about this as I have suspected it of myself but no way to prove it than to test again & again & again which is something I'm not willing to do.

[greenbeanie]

Thanks for your reply, squimingitch - and I'm so glad you're safe from Irma!

You got me thinking about iodine again, and that may be the culprit. I had been so happy with the huge improvement after going gluten free that a little itch now and then was tolerable. But I haven't really been avoiding iodine aside from buying non-iodized salt, and maybe I've become more sensitive to iodine with time. At various points I have suspected dairy, fish, potatoes, eggs, and salad. I didn't realize until looking it up again now that potato skins are high in iodine, and I wasn't thinking of iodine as a common feature of all those things. So when I tried to test the dairy theory by eliminating it for a week, for instance, I was probably eating more fish or eggs for protein. Same thing when I eliminated eggs - I don't really remember, but it's likely that I was eating more of the other foods. I concluded at the time that dairy (and then eggs) wasn't the culprit after all, but I might have just replaced one source of iodine with another.

 

Antihistimines definitely make my rash flare (and the ones I was taking recently don't contain any iodine/iodide), but maybe that's just because antihistimines can be drying in general. My skin isn't particularly dry, and lotions have no effect whatsoever, but I can see how the internal drying effect of antihistimines might aggravate any rash.

 

Well, new theory to test! I'll try a low-iodine diet for a couple weeks and see if that helps. Thanks again for the suggestions.

[Victoria1234]

During the first few gluten-free years, if I had a crumb, or in some instances even gluten-free food that must have been closer to the 20 ppm, my rash would either itch but not show up (magically alerting me almost immediately) or come back a bit. It took hardly a thing to activate it. I was soooo sensitive I avoided all packaged gluten-free foods. Then eventually I stopped being so sensitive. But it took years. I actually miss the bit of itch that would alert me, as now I don't seem to react at all. And I can't be doing years of perfect, gluten-free living in a shared household?

[greenbeanie]

It's encouraging that you stopped being so sensitive to gluten-free packaged foods with time, Victoria1234! I live in an entirely gluten-free household, fortunately, so we have no worries about cc here. My daughter and I both had trouble with gluten free foods made in shared facilities, even those testing below 20ppm, so we eliminated almost all packaged foods for quite a while. We do have some occasionally now, but only things that seem very low-risk (like small amounts of mustard labeled gluten-free that's not made in a dedicated gluten-free facility), etc. We've been doing that for more than a year with no problems, though - and my daughter is still fine now, so I'm pretty sure my recent rash recurrence is not a cc issue from food.