I am allergic to something in my apartment but i can't tell what!

Stuff can be in air ducts; that's usually what gets me when I can't see anything but still get a reaction. I assume you don't have a roommate and haven't changed soaps/perfumes (some perfumes set me off worse than entire forests.) Also, is there any chance the dog is bringing stuff in? I can't tell from your question, if this is literally one sick room in a fine house or a larger problem. One sick room says "check air ducts, light fixtures, and wash everything in hot, hot water" to me. Bugs can be very small and mold sets me off before I can see it. Unfortunately, mold can be behind walls. You don't happen to be adjacent to a bathroom or other wet space, right?

Mold is usually hard to see. Roach allergy (me too!) is really an allergy to frass, which is the excrement and broken exoskeleton. Dust allergy, similarly, is to dust mites and their frass. Advice from my ENT was: dehumidify, stop eating cheese, and keep the dust to a minimum with a good quality HEPA filter. For symptom management, I rotate through benedryl, claritin, and whatever other antihistamine is on sale at a discount.

By hard to see, I mean absolutely invisible to the naked eye.

thanks guys! this is a small room in a small-ish two bedroom apartment, but it's not next to anything wet. I think it's a "one sick room" because i don't have the same problem in other parts of the apartment, although i don't spend very much time outside of my room so I don't know for sure! I am probably going to have to get another kind of med to rotate with claritin, because they (the 24 hour kind) are barely lasting me 12 now!

Maybe look into an air purifier, then see if you can have what gets trapped in the filters tested.

Oh, and this is counter intuitive, but if you're also allergic to pollens, don't open the windows. Run the HEPA filter all the time. For dehumidifying, you can get a product called damp rid, and/or buy a machine.

I am probably going to have to get another kind of med to rotate with claritin, because they (the 24 hour kind) are barely lasting me 12 now! See an allergist. They can prescribe different medications that are more helpful than Claritin (like Singulair), they can test exactly what you're allergic to (so you can take appropriate mitigation measures), and they can start you on allergy shots so you don't need meds (after a few months).

I just moved to New York and have the same problem, and the girl who lived in my apartment before me says that she was "allergic to New York" for about two months when she moved here. It's pseudosciencey, but I think I might just be getting used to the pollution in the air and dust here. Cleaning and vacuuming a lot (including vacuuming my bed) seems to help somewhat.

Do you use an air conditioner or an fan? Fans tend to kick up everything you could possibly be allergic to and redeposit them right in your face. A cheaper option than Claritin that (for me and others I've polled) works exactly the same (because it's the same thing): generic 10mg loratadine from any drug store. If it's not going to last you the full 24 hours, it might as well be cheap.