I used to love to be able to keep my windows open in the spring and fall, but since I developed allergies I am no longer able to do that. Not only would I get the scratchy throat and swollen eyes, but sometimes I would also break out in an allergic rash.
When I am inside, keeping the air conditioner on helps. If I am going to be outside for an extended period of time, I always take some medication before I go outside to help control the symptoms. It can get kind of frustrating, but is better than suffering the miserable consequences.