Snorting.. ahh yes, Louis had that bad last spring. I used this website and gave him benadryl:
http://www.geocities.com/angeljulie2/firstaid.html
I took him to the vet before I gave him this, of course, and he said it was fine because it was allergies, it cleared up thereafter. It was scary though because of the hacking and the foamy, sticky thing...
Either way it would be a great idea to take him to a vet before you make any attempts on anything, Sometimes just calling the vet and asking the vet tech if it is a common concern now a days for the pups due to the time and season.
Hope your baby feels better soon!