HGH has antihistamine formulas to look at. My spouse has been managing his allergy symptoms for 20 years with just stinging nettle. Usually by August he’s taking nettle daily through the first hard frost, earlier if it’s a heavy spring pollen. It significantly lessened his reactions, just give it a week or so to build the tolerance in the body. Eating local raw honey is often suggested as a way to get a body adapted to seasonal pollens as well.