Yes I have a great remedy, however you already ruled it out.
Allegra or Zyrtec or Claritin (second generation antihistamines) work well for me. My personal preference is Allegra. I would try all three if one does not work well for you after taking it for a few days. Start with trying the name brand, if one works, then switch to the genetics. Theoretically generic and name brand are the same, but for some people only the name brand gets results. They generally do not make people drowsy, even at much hire doses than OTC, but it is not an impossibility. If they do, try taking them at night as it is a 24 hour med and by morning you might get the benefits without the side effects.
Stay away from anything with first generation antihistamines like benadryl, they give no better results and have a lot more side effects.
Edit: seasonal allergies cause nasal congestion, shortness of breath is more likely asthma. You should see a healthcare provider for PFT and bronchial provocation testing.