If I dont my eyes swell up and Itch. Once when I lived in SF my girlfriend (now wife) got a hand me down rug from another tenant. I walked in the room and immediately could feel it in my eyes and said CAT. She said, how do you know? I told her and she said the person who gave it to her had a cat a year ago and had washed the rug. No good, Im that sensitive. And yes I suffer incredibly this time of the year with hay fever and allergies to every blooming thing. Eye drops, nose spray and Zyrtec every day.