Wait. You're allergic to most meds?
I wonder if you're allergic to the excipients in the actual capsules/tablets. For example, a lot of OTC pills are actually filled with lactose, so anyone who's lactose intolerant will have serious issues with a lot of OTC pills.
Can you do an allergy test to see what you're specifically allergic to? Maybe you can figure out what's going on and then see if you can possibly find a med that
doesn't have the allergen in it?
I don't know about medication shots, but have you looked into those? They may not have the excipients in them that you're allergic to.