Natural vitamin C has completely gotten rid of my hay fever. And now to think of it, I'm not at all sensitive to dust anymore.
See article "Vitamin C vs. Ascorbic Acid" here for superiority of the natural complex with bioflavoniods:http://www.radiantlifecatalog.com/wh..._ascorbic_acid
Quercitin is along the same lines, but I prefer to take whole C which has a mix of bioflavonoids, including quercitin.
I take 250mg./day of natural C (I've used amla, acerola and camu at different times, all effective) when I feel I need it, which is the max dose. I usually take a maintainance daily dose of less than that. When I slacked on it, taking little to none this spring, I noticed my hay fever coming back (itchy eyes, sneezing, throat tickle) ... and it's completely gone again w/in a day of resuming my max dose.
There are older studies that show that C is very effective for seasonal allergies, but as we know, modern medicine discounts real nutrition that the human body has run on for millions of years.