Curious if anyone has had to use medication for their dogs seasonal allergies, if so what do you use? Every year around this time my daughter's mini aussie has fits with itching, etc. This year seems to be the worst. The vet said to try Benadryl, Chlorpheniramine, or Zyrtec. We've tried Benadry and Zyrtec and no luck yet, going to try Chlorpeniramine next.