While this is an interesting link HerbGuy, the first thing I looked at (in order to get a feel for this website) was supportive of pharma-meds for animal allergies! http://allinfoforyou.com/cat-or-dog-allergy.htm I myself prefer Goldenrod, amongst other things.
To be fair, I am also somewhat of a purist when it comes to this, as I have found for myself that chemical medicines only mask symptoms, where herbs and other vitalistic therapies (nutritional or energetic) address the underlying issues and support the healing/cure of the condition. The only pharma-medicine I am aware that does not just mask symptoms would be antibiotics - and while it can kill infection, it kills all the good flora while allowing yeast to overpopulate. Again, I prefer herbs, and nutritional/energetic therapies. Thank you!