Welcome ceebee,
Air Purifier I believe they work good. I bought mine from Target. I cannot afford to buy one from an allergy store. Mine seemed to clean the air I had less problems when I was running the machine it seems. Have to keep the filters clean and changed as directed. Otherwise, that dirt goes out into the air. Allergy tests would be good if you haven't already. I have no carpet in my house, and it is easier to keep clean for one thing. I think it helps my lungs also. I use a good nasal prescription spray for my congestion in nose.
Hope, things improve for you. Best Wishes!! Happy 2007!! Brandi...