Hey I had a problem with this allergy stuff before but it sort of vanished as I grew older and I don't have a problem with it at all anymore. So, if you are still under 20 then you might grow out of it like I did but even if you don't, you would still be good to go for aviation as long as you can control your allergies with medication like claritin/allegra/nasonex... There are a bunch of different allergy medications the Marines will accept so I wouldn't worry about it too much. Instead get in shape and do well on the ASTB. GL.