Why doesn’t repeat exposure to an allergen build resistance to it? And why are there no allergy vaccinations? /u/wilderneyes No such thing as stupid questions

Both allergic reactions and sickness involve responses from the immune system. And allergies often get worse with repeat exposure, but repeat exposure to an illness builds antibodies and your immune system is able to handle it better. Why doesn’t that work with allergies? And why can’t we build resistance to them via vaccines or exposure the way we can with sickness? If the body “fights off” peanuts or shrimp or whatever once, why is it worse at dealing with it the next time? I’m just curious what the difference is.

Both allergic reactions and sickness involve responses from the immune system. And allergies often get worse with repeat exposure, but repeat exposure to an illness builds antibodies and your immune system is able to handle it better. Why doesn’t that work with allergies? And why can’t we build resistance to them via vaccines or exposure the way we can with sickness? If the body “fights off” peanuts or shrimp or whatever once, why is it worse at dealing with it the next time? I’m just curious what the difference is.