I finally think I just solved the problem of the Runny Nose. After a few trips to the Vet two weeks of antibiotics, and lots of frustration. My 5 month old Greater Swiss Mountain Dog is booger free.
From the moment we took Moby home at 8 weeks he had been sneezing. As he grew the sneezes became more frequent and were often accompanied by huge volumes of brownish yellow snot. My fears only continued after visiting the vet, and he was unable to determine the cause and most importantly the solution. We tried Claritin, antibiotics, he had been on raw food, switched to Blue Buffalo kibble, the snot and sneezes kept coming. We were certain that we were to have 130 lb. dog with excessive amounts of snot that could appear at any given time.
Finally, I began to examine the snot instead of just cleaning it up. It appeared that there was food in it.
Because he is a large breed dog I was trying to slow down his eating and keep his food on the floor. I raised the bowl so his snout was not buried in the food. Additionally I switched to Royal Canin which has a much larger kibble size than most current dry foods.
After two days I am happy to determine that he is basically snot free and the problem is solved. I worried that this condition was indicative of something far worse. SO PLEASED WITH THE RESULT.
If your dog has a runny nose and is sneezing. Check to see if he is sucking the food into his nose before you panic.