January's issue of the Journal of Allergy and Clinical Immunology is dedicated to immunotherapy. To be honest, the first time I heard of immunotherapy, I thought it was a quack treatment (it didn't help that what I'd heard of was sublingual immunotherapy, and the point of the author was that because the FDA hadn't yet approved it in the US, it must be too effective). But the more I learn about it the more I find that it is a long-established therapy with proven results. You should read the issue's editorial, which summarizes immunotherapy over the past 100 years.
What did I learn from this issue? (Not: what is news to everyone; what was news to me.) First, it seems that immunotherapy is largely directed at allergic rhinitis, or hay fever, caused by grass pollen; that, in the US, the standard method is repeated injections over a long period, from four months to three years; that sublingual immunotherapy is widely practiced in Europe, and appears safe and effective; and that trials of therapies for other allergens such as cat dander and dust mite droppings are being conducted and show promise.
For now let's leave aside the issue that doctors don't seem to be prescribing immunotherapy for eczema patients. Say it were available. What then?
The problem for me is that I don't know for sure what allergens cause my eczema. I know that my skin prick test, 10 years ago, showed that I reacted to a bunch of things including cat (at least, one cat allergen), egg white, and rye grass. But does that guarantee that, say, rye grass pollen is a major factor in my eczema during the period that rye grass pollen is in the air? Everything I've read regarding food allergies says that skin prick tests are not diagnostic, and that the gold standard is to lay off the offending food and see if the problem goes away. There's no good way to try an avoidance diet with pollen or dust mites.
An aside: the reaction I get in the spring and summer, which I attribute to pollen, is quite different from the eczema I experience on my hands, arms, scalp, etc. In the summer, on both east and west coasts, I get red, inflamed skin on my face in a butterfly pattern. It's distinctive, and out there in the open for everyone to see. I saw the same pattern once on someone else's face.
One thing I am sure of: Claritin and Allegra, the over-the-counter antihistamines marketed for hay fever, do absolutely nothing for me.
Would I undergo injection immunotherapy, a long, arduous, and (in the US) expensive procedure, in the hope that 1) the thing I'm getting injected with is a major contributor to my eczema and 2) the therapy works for me? No, I wouldn't. And I do suspect that at least one form of pollen gives me trouble.
But I would take a course of immunotherapy tablets orally (or sublingually). That would not seem like a waste of time, nor would it be hard to get a kid to take them. One good thing is that grass pollens are, apparently, "cross-reactive," which I read as meaning their allergens are similar enough that if you induce tolerance to one, you induce tolerance to the rest of them. So you don't have to take more than one type of allergen as immunotherapy.
Reading the editorial, I did learn that grass pollen tablets are not effective if you take them as only one component of a mix of allergens in immunotherapy. Here's another difference between the US and Europe: in the US, a multiallergen mix is a common approach, while in Europe, immunotherapy for a single allergen at a time is the norm. (Any experts or Europeans are free to correct me on this.) So, it does appear that the US is lagging Europe in easy, effective immunotherapy.
When will we see immunotherapy applied to eczema? Is there anywhere in the world where it already is?