Allergy shots require many injections over long periods of time to be effective. Why can't the body get over an allergy with just a couple of injections?
What will be an ideal response?
Allergens react inappropriately with mast cells, which then release histamine, a vasodilator. The inappropriate reaction cannot be undone, so the idea is to try to prevent the reaction from happening. Allergy shots are a form of vaccination against the allergen itself. Repeated low exposures to the allergen will stimulate the production of IgG antibodies. If the antibody levels can be repeatedly increased, any allergen that makes it into the body will be neutralized before it can interact with the mast cells and trigger an allergic response.
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