I'm not sure if I'm allergic to anything, except I have bags under my eyes that are apparent with my glasses off, and these are caused from my allergies to airborne things like pollen I suppose.
I also think I may be midly allergic to nickel, as I have a sterling silver necklace that I've had on for months and I've just taken it off because I had a rash on my neck months ago and now it's a spot that just won't go away. I guess I'm the lucky 15%.