OK, a few good things (apart from the usual chemical bombs) are:

- get yourself some chromoglycin (google it; I only know the brand names here in Germany - Pollicrom). That's a molecule that will harden the skin of the immune cells that normally explode and release histamine when they encounter an antibody. Note that you have to take that a few weeks BEFORE the season starts. Once histamine got released, the inflammation is kept alive by other signalling mechanisms. Suppression of histamine after inflammation start doesn't work well.

- there's an emulsion of sesame oil and mint available, that you spray into your nose. It creates a sticky layer and the pollen will get attached to that and not enter skin/body. Works very well. Brand name in DE is "Abtei Allergie Nasen Schutz Gel". Should be available world wide, more or less.

- Eat lots of quail eggs. Not kidding.

Good luck, buddy