I have allergies year round from one thing or another... but for summer/spring pollen allergies i just learned a great tip:
Honey. Locally harvested only. Use it in cooking and whatnot, or, if you're like me and are sneezing from the time you wake up, take a teaspoon of it in the morning and again whenever you get another attack.
It makes sense: local honey bees harvest pollen from local flowers, presumably ones you're sneezing about, they bring that pollen back and make honey out of it... local growers/farmers harvest that very honey and sell it at local farmer's markets. You eat that honey and you build up a tolerance to the local pollens. Best to get wildflower honey. If the farmer has the option, pick late harvest or early harvest. The people this last weekend had that option. I picked up a fair amount of late harvest honey for a decent amount of money on Saturday morning. Farmer's markets... seriously...
I first learned of this on the show Good Eats on the Food Network. Alton Brown has lots of funky little tips about food. so now, I hit the farmer's market.
Granted, this won't help my dust allergy... of course cleaning is the only thing that'll help that... HA!