Allergy shots seem to modify how the cells react to the signal the IgE gives them. In other words, not as much histamine is released. How and why this occurs is still not understood very well. With these things working for you, you would expect that shots would solve most of the problems with allergies. Unfortunately, it is not as straight forward as you might expect. Here are some pitfalls:
- It takes about 3-9 months of continued allergy shot therapy before the above effects peak. Therefore, it requires a lot of patience and watchful waiting. And after all the waiting, there are some children who may have no noticeable effect in symptoms.
- You will notice that my example was with someone who was allergic to one particular thing (oak pollen), and that example is of something that is prevalent once or twice per year. Many children are allergic to things that are in the environment all the time (e.g. dust mites, animal dander, certain pollens, etc.). In addition, many kids are allergic to more than one thing. In these instances, there is a lot of conflicting evidence as to whether allergy shots even work.
The latest in this controversy was published in the New England Journal of Medicine