Horse Veterinary Questions? Ask an Equine Vet.
My name is ***** ***** I have been a Vet tech for 30+ years and a Horse owner for over 45 years.
A horse that has any wind obstruction or breathing issues is called Wind broke. In a case like this I would have your Vet out for a soundness examination, before making any decisions. I personally would be hesitant and not go on hearsay that it is allergies. There are too many things that can cause obstructive breathing and shortness of breath. The Vet bills can be astronomical if an serious obstructive disease like Asthma.
I would call in a reputable Equine Vet of your choosing, for an independent Soundness exam and if need be to check the bronchial passages. Better to check prior to buying than being stuck with major issues later.