I completely agree that it is an allergic reaction because it is at the same time every year (though last year it was early due to the record heat here in Milwaukee) and lasts exactly 14 days every time. The occurance is usually mid-Sept. He's had chest exrays 2x, and last year had some sort of "scope" procedure ... lungs are always clear.
One added complication is that, a couple of years ago, he contracted Lyme disease. He came down with it in late spring, was treated and recovered. However, last year it recurred at the same time as the malady ... what a horror ... he actually was unable to breathe long enough that he passed out, and then had a siezure.
Isn't there an allergy drug for late season allergens that alleviates "asthma" type attacks as opposed to rash or cough?
I currently go to a "regular" vet. Do you think there would be any advantage to going to a "holistic" vet instead?