Boy, do I have a lot to say on this subject! I have allergies and five cats. I can give you several pointers holistic and over the counter to help you combat this as they have immensely helped me. I almost have no symptoms whatsoever now. You may not need to do all of these as I suspect you probably don't have as many cats as I do but if you do, I think it will make a huge impact on your allergy situation.
There is a miracle product called Sneeze No More that is a spray you can get to spray in the areas where you cat spends the most time like on his bedding and sleeping areas. You can search on Google for it or you can get it off our website at www.houseofmews.com
in the shopping area. Our shelter really works with people who want to keep their cats and we decided to sell this product because it was so remarkable. It may seem expensive ($20) but it last a long time.
Also, I got a small air purifier from Sears that I put in the main room of our apartment. It has made a huge difference.
I do not let my cats in my sleeping area unless it is when I am reading or want to spend special time with them. I keep my bedroom door shut when I am not at home to keep them from lounging on my bed and pillows.
Two drops of vinegar a day in their water made a big difference as well. A holistic vet recommended this to me. A lot of people think it is the hair and dander that you are allergic to but sometimes it is the protein in a cats saliva. When grooming themselves, this protein is spread over their body thus if a cat has long hair, the more protein that will be spread. The cats really won't like it the first few days but now my cats know no difference. The vinegar breaks this protein down and is not harmful to the cats at all. Good luck!!! Hope this helps!