I found that when my dog was younger, I was more allergic, and even her saliva would make me itch. I guess I became immune, as I'm not overly allergic to Indy anymore, or Max the GSD when he came.
Cats however, are just the opposite -- I'm not allergic to kittens, as they don't groom themselves, so they don't have reminants of saliva on them. My allergist told me that once allergic, there are three things that will trigger the allergy: dander, saliva, and their urine.
stick75, a lot of it depends on where the dog lives (indoors or outdoors) in terms of what allergens stay on them. I'm a very allergic person, but adding the GSD didn't add much to my allergy load. However, they *do* shed. You can reduce some of that with a good diet and grooming.