Multiple. Any of the otc allergy medications, such as claritin, zyrtec, or Allegra will help. For eye symptoms, try zaditor (ketotifen).
All of them. A lot is said about the different allergies, but the mechanism that causes allergy symptoms is the same regardless of allergen. Some people may be more allergic to different allergens, so it's easy to see why one might think that zyrtec (cetirizine) works for grass pollen allergies and not for their cat allergy. But the difference is that they're more highly allergic to cat, not that zyrtec (cetirizine) doesn't work for it.